Ahh, missile defense

At the suggestion of my colleague, I want to draw your attention to a very interesting and fun article in today's New York Times (free reg. required). It's about an antimissile laser system developed jointly by the US and Israel. The system works, basically, but is hugely expensive and so large in physical size that deployment is a nightmare. The article is really worth reading, just for the paragraph that begins: "As often happens in the federal development of death rays, parts failed and costs soared."

This week in cond-mat

A couple of new papers on the arxiv that I find particularly interesting....
cond-mat/0607756 - Zarchin et al., Bunching of electrons in transport through quantum dots
The Weizman Institute's work on transport in quantum dots is generally as good as it gets. I've already written about their experimental prowess in measuring shot noise, and this is another example. Shot noise results from the discrete nature of electronic charge. While the current tells you about the average rate at which electrons are flowing through a circuit, there are fundamental fluctuations in that current that describe the temporal correlations between the electrons. For example, if electrons only flowed through the circuit one at a time in perfectly spaced intervals, there would be no noise. On the other hand, if the electrons were Poisson distributed, there would be a classical current noise of 2eI (in units of amps^2/Hz). The authors here looked at shot noise in gate-defined quantum dots on GaAs/AlGaAs 2d electron gas. The authors found a surprising result. In the finite-bias conductance resonances that happen in these kinds of dots (as the source-drain bias is increased to allow access to another charge state for transport), the shot noise was enhanced over this classical result by as much as a factor of 10. This implies that the electrons are bunching up somehow, traversing the dot in bursts. This is quite odd and unexpected.

cond-mat/0607765 - Kitchen et al., Atom-by-atom substitution of Mn in GaAs and visualization of their hole-mediated interactions (also out in Nature)
This is a very nice STM paper by Ali Yazdani's group from Princeton. These folks are able to insert single Mn atoms into the surface of a p-doped GaAs wafer, and watch what happens. This is important because ferromagnetic semiconductors like GaMnAs are a key class of materials for those interested in capitalizing on the spin as well as charge of free carriers. What I really find interesting about these measurements is how very different a dopant atom in this semiconductor system looks from the puffy, hydrogenic picture painted in solid state physics textbooks. These kinds of results always re-emphasize to me that serious STM can't be your hobby - it has to be the main focus of your research effort, or you can't be competitive.

What the...?!

I thought I'd seen it all this evening when I opened my email to find an extensive warning email about laser pointer safety (!) from the SPIE (presumably sent to me because I'm speaking at an upcoming meeting, not because they think I'm a danger to myself and others when armed with a laser pointer). Remember, laser pointers are all fun and games until somebody loses an eye. This warning actually did include the sentence "NEVER stare directly into the beam of a laser pointer!". Whew! Good thing they warned me, in case my advanced degree hadn't given me sufficient critical thinking skills to reason that out for myself. The last line of the email made clear the real reason for sending it. They boldly declaim that any person using a laser pointer at an SPIE event but not adhering to the outlined safety protocols is personally liable in the event of injuries, and the SPIE is not liable. I consider this direct observational proof that our society has too many risk management and personal injury lawyers.

That paled compared to my reaction to this story, though. It would appear the Purdue University has done a thorough and careful investigation of claims of research misconduct in the case of Rusi Taleyarkhan, the scientist who claims to have used sonoluminescence of deuterated acetone to produce table-top-scale fusion. In the spirit of scientific openness and transparency, Purdue has decided to not make public the result of its investigation. So, either Taleyarkhan is legit, and Purdue is content to let his reputation suffer, or they think he's a fraud, but are content not to tell the scientific community, or some mysterious third alternative. What on earth is Purdue's administration thinking with this? Did they assume noone would notice?

This week in cond-mat

Just two papers this time. For the first, I must make a disclaimer: this is certainly not my area of expertise, and I can't really judge the validity of the results, but the topic is very interesting. I also haven't read either of these in any detail - they just look intriguing.

cond-mat/0607492 - Joly et al., Liquid friction on charged surfaces: from hydrodynamic slippage to electrokinetics.
I vividly remember a great APS meeting talk by Seth Putterman (I think 10 years ago at the big centennial meeting in Atlanta) on basic pieces of table-top physics that we still don't really understand. One that he mentioned was triboelectricity - the separation of charge due to some frictional process. Remember junior high when you were told to rub a lucite rod with rabbit fur to build up a static charge? Amazingly, we still don't really understand the microscopics of this (unless the situation has changed recently. Any enterprising readers out there know anything about this?). Anyway, this paper is about the fluid analog of this. When a fluid containing ions is placed in contact with the walls of a container, the ion distribution is altered. Depending on the microscopic details of the fluid and the wall material, a sub-monolayer of charge can become practially immobilized at the wall (the Stern layer), and beyond that there extends into the fluid a net charge density (decaying exponentially into the fluid on a scale called the Debye length) set by competition between charge screening and diffusion due to concentration gradients (the appropriate diff-eq is the Poisson-Boltzmann equation). All this stuff is very important when worrying about colloidal suspensions, net charge on nanoparticles in solution, electrochemical scanned probe, etc. When fluid is flowing, slippage of the fluid layer right next to the wall can strongly modify the ion concentrations, and this can have big consequences for electrokinetic processes like electro-osmosis and electrophoresis. That's what this paper is on, and it's directly relevant to lots of micro- and nanofluidics work going on, particularly in the lab-on-a-chip community.

cond-mat/0607354 - Qi and Flatte, Current-induced spin polarization in nonmagnetic semiconductor junctions
Kato et al. showed recently that it's possible to build up a net spin polarization in the carriers in a strained nonmagnetic semiconductor (e.g. GaAs) by applying an electric field (and hence driving current into one side of the semiconductor through a junction, and out the other side). Lots of questions were inspired by this - is this a spin-orbit effect? Is this a spin-Hall effect? Now this new paper argues that the effect is neither of these things, and happens even in the absence of spin-orbit effects and for purely spin-independent scattering mechanisms. The trick seems to be that the mobility of carriers ends up depending nontrivially on the spin polarization (see here) for reasons that I don't currently understand. Seems profound enough that I should try to learn about it, though.

A time-saving step

This weekend I'll catch up w/ the cond-mat archive. In the meantime, I wanted to point out one amusing piece of Lubos Motl's latest blog posting:
The previous paragraph also clarifies my style of reading these papers. The abstract has so far been always enough to see that these fundamental gerbes papers make no quantitative comparison with the known physics - i.e. physics of string theory - and for me, it is enough to be 99.99% certain (I apologize for this Bayesian number whose precise value has no physical meaning) that the paper won't contain new interesting physics insights.
This attitude is surprisingly common among physicists. In a graduate seminar course at Stanford, someone else in the class showed our (then pre-)Nobel Laureate theorist professor a paper on high temperature superconductivity. After glancing at the title, author list, and abstract, he tossed the paper face-down on the table, and said, "I don't even have to read this to know that this is crap." Sometimes this approach (or its converse) really does work. I certainly have a list of condensed matter and nano experimentalists whose work I presume to be extremely good, because everything I've ever seen from their research groups has been elegant and solid. However, pre-judging results based on who did the work and what the abstract says is exactly the kind of non-scientific, unobjective attitude that emboldens social science types to argue that science and its findings are largely a social construct, etc., a conclusion that I think is way off base (when I drop my pencil from above my desk, it will fall toward the ground at 9.8 m/s^2, regardless of my sociology, preconceptions, or personal beliefs).

A couple of random things

One of the more popular physics blogs, Cosmic Variance, has an interesting post about rumor mill websites. If you aren't familiar with the concept, rumor mill sites have been around for a number of years associated with physics and astrophysics faculty job searches. The atomic/molecular/optical and condensed matter rumor page is here. Mark over at Cosmic Variance has interesting things to say on the subject.

Also, as a follow up: I did hear back from Phys. Rev. Letters about the possible data falsification that I pointed out to their editors. They heard back from the authors of the paper in question, and say that the authors showed them "raw" data, and that it was some sort of image processing artifact that made all the noise in the relevant images really look identical. Hmm. I'm unconvinced, but the editorial office says they're satisfied. If anyone wants to see the paper in question, contact me.

I'll put up more cond-mat and physics related postings soon; I need to tend to a couple of papers from my students, as well as a not-so-minor crisis involving our cleanroom facility.

Conference proceedings

I'm working on a conference proceedings paper for a meeting at which I'm giving an invited talk next month. So, are conference proceedings papers worth it? Does anyone actually read these things, even the ones published in peer-reviewed form? Or are they part of a borderline sleazy scheme by some professional societies and journal publishers (hint: I'm thinking of one that begins with "Elsev" and ends with "ier") to extort money from cash-strapped libraries for volumes noone ever examines? Also, what is the appropriate ettiquette regarding these? I get the impression that many of my colleagues would have no problem either farming out the writing to a student (even though they wouldn't get first authorship), or just bailing on the whole proceedings altogether (which I confess I've done before, too, when other demands on my writing time get too big). Opinions, anyone?

This week in cond-mat

Just returned from the Electronic Materials Conference. Interesting, and generally much more oriented toward engineering than pure physics, but fun nonetheless. I'll be out of commission for the next week or so, so this blog entry will have to tide over my dedicated readership :-)

cond-mat/0606742 - Camino et al., Transport in the Laughlin quasiparticle interferometer: Evidence for topological protection in an anyonic qubit
In the fractional quantum Hall effect, in very clean two-dimensional electron systems (typically formed at the interface between GaAs and AlGaAs layers) at very low temperatures and particular large magnetic fields, the "normal" metallic state of the electrons is unstable. The particular values of magnetic field are those for which the ratio of magnetic flux through the sample (in units of h/e, the so-called flux quantum) to the density of electrons (number of electrons per cm^2) takes on special values, such as three or five halves (corresponding, respectively, to three flux quanta for each electron, and five flux quanta for each pair of electrons). At these special values of magnetic field, the electrons form a correlated state named after Bob Laughlin, who first wrote down a trial many-body wave function to describe it. In a Laughlin state, the electrons can't be treated as nearly independent, as in a normal metal. Instead, when one tries to probe the electronic system, one finds collective excitations (rather than simple electron-like excitations in a normal metal). These collective excitations have very funky properties: they can have fractional charge (in the three flux quanta per electron case, the excitations have charge 1/3 e) and obey fractional statistics.
Fractional statistics are funky. Swap two electrons, and the total wave function picks up a factor of exp(i pi) = -1. Swap two bosons (like two 4He atoms), and the total wave function of the boson system picks up a factor of exp(i 2pi) = 1. Swap two Laughlin quasiparticles, and the total wave function picks up a factor of exp(i alpha), where alpha depends on precisely which fractional state the system is in. Generically alpha can be anything, earning the nickname anyons for particles that obey such statistics.
This paper looks at conductance oscillations as a function of magnetic field in a patch of Laughlin electron fluid that should exhibit fractional statistics and fractional charge of 1/5 e. The authors claim that these oscillations are surprisingly robust as temperature is increased, and that this is evidence of special stability of that state due to topological considerations. I'm not sure I believe the final conclusions, which seem to depend in great detail on precisely knowing the electron temperature. It's a neat experiment, though, and gives real insight into some exotic quantum effects that people think might be useful for building a quantum computer.

cond-mat/0606802 - Costache et al., Spin accumulation probed in multiterminal lateral all-metallic devices.
The authors in this paper look in detail at the magnetoresistive properties of a little piece of aluminum connected to four separate cobalt electrodes. It turns out fortuitously that each of the four cobalt leads can have its magnetization switched independently of the others, and this lets the authors study effects that arise from pumping certain spin polarizations of electrons into the aluminum island. Since aluminum is a low atomic number material, spin-orbit scattering is pretty weak in there, so electrons can maintain their spin polarization for a while. These experiments require extremely clean interfaces between the Co and the Al to work, and provide concrete numbers for spin lifetimes and diffusion lengths in practical materials.

This week in cond-mat

Two interesting papers relating to mesoscopic physics on the arxiv this past week:
cond-mat/0606486 - Jakobs et al., Temperature-induced phase averaging vs. addition of resistances in mesoscopic systems
Classically, electrical conduction is well described by Ohm's Law. Take two resistors and put them in series, and the total resistance is just the sum of the two individual resistances. In the quantum world things are more complicated. Imagine an electron incident on a tunneling barrier, such that there is some tunneling amplitude t for transmission, leading to a transmission probability of |t|^2. Now consider two such barriers in series. Classical expectations would lead you to expect a transmission probability for the two-barrier system to be (|t|^2)^2. In fact, depending on the details of the system (the incident energy of the particle, the barrier heights and widths, the separation between the barriers), the full quantum treatment can give transmission probabilities ranging from zero to one (!), because of interference effects. These can be constructive or destructive, depending on just how the multiply reflecting waves bouncing back and forth between the two barriers sort themselves out, in terms of phase differences racked up. On the macroscale, inelastic interactions with the environment act to randomize the relative phases of those waves, washing out interference effects and restoring the classical Ohm's Law result. This is treated really well by Datta in one of his books. Anyway, this paper considers just what happens at finite temperature, even in the absence of true decoherence. Because electrons that dominate conduction have a spread in energy of around kT, they have a spread in wavelengths, and effectively a spread in their phase accumulation as they bounce around between scatterers. This paper looks at the effect of that averaging on the addition of resistances.

cond-mat/0606473 - Gao et al., Cotunneling and one-dimensional localization in individual single-walled carbon nanotubes
This paper is related, in the sense that it actually looks at the temperature dependence of conduction through a one-dimensional system containing randomly distributed scatterers. In this case the system is a single-walled nanotube, which really has 1d band structure because of its geometry. The scatterers are defects or disorder, and the tubes in question are around a micron in length. Gao et al. find that the tubes exhibit activated transport (becoming exponentially more resistive as T approaches 0), though the activation energies can change as temperature is reduced. At the low temperature end they find that the tubes effectively have broken up into a 1d array of quantum dots. They argue that the varying activation energies happen as the effective dot size changes with T. As temperature is decreased, coherence is increased, and higher order tunneling processes ("cotunneling") can enhance interdot conduction. A neat result and a nice idea, though their Fig. 1 raises a common issue that comes up in many such measurements. They take a log-linear plot of resistance vs. 1/T, and have "guide to the eye" lines indicating regimes of different activation energy. Are there really clear multiple regimes, or is the effective activation energy smoothly varying over the whole range? Lines to "guide the eye" should be used with caution....

Voting in this country

I try to keep political commentary to a minimum on this blog, because there are plenty of blogs out there dedicated to that kind of discourse. I do have one observation to make, though. When considering modern politics in the US, what does it say about a political party that an apparently legitimate (that is, recognized, orchestrated, and encouraged at the national level by party leaders) part of their strategy is to suppress voter turnout? It's one thing to try to pander to -- err, energize your base to make sure that they come to the polls in droves. It's quite different to deliberately try to keep people that you think might be voting for the other side away from the polls. You know, by tactics like phone bank jamming sanctioned by the White House, blanket scrubbing of voter rolls in ways virtually guaranteed to bar legitimate voters, shredding voter registration cards of people from one party, challenging the legitimacy of every ballot cast in certain precincts to deliberately slow down the vote in areas dominated by the other party, etc.

NASA and statistics

On NPR this morning I heard NASA administrator Michael Griffin explaining why he thought it was ok to dismiss safety concerns raised by two of his managers regarding the upcoming shuttle launch. He said that since they'd had 114 flights and never lost a vehicle due to the particular problem area identified by the managers, he found it "unreasonable to think it was likely" that they would lose one in the future. There are so many things wrong with that reasoning it's hard to know where to begin. Couldn't his (2x) predecessor have said almost exactly the same thing about any foam falling off the external tank prior to the final flight of Columbia? Has he ever heard of Poisson statistics? As my thesis advisor said while on the Columbia Accident Investigation Board (Times of London, April 30, 2005): "[T]he risk of a serious failure is between 1 and 2 per cent a launch, or between 24 and 43 per cent over the 28 missions still planned"
Griffin's no dummy - what he really wants to say (but can't do so explicitly because it would be so impolitic) is that he considers the risks acceptable, given that the alternative is to declare the shuttle program done because they can't retroactively fix this design flaw. What a mess.

physics sociology

There's been a brewing discussion going on, largely and appropriately in the high energy physics community, about string theory - does it actually have reasonably specific, testable predictions? If not, is it really science in the classic sense?

People can become incredibly personally vested in their ideas in science. In physics in particular there can be a tendency to assume (a) that you're right (duh!), (b) that your ideas have been arrived at by a careful intellectual process (duh! again), and (c) therefore anyone who disagrees with you is either ignorant, not very smart, or hasn't been thinking about things "the right way" (read: your way). Reminds me of Vizzini in The Princess Bride: "Ever hear of Plato? Aristotle? SOCRATES?! Morons." Prior to today, the best example of this attitude that I'd ever seen was at a talk given by a job candidate, who, when asked a very good question by one of my very respected colleagues (who happened to be on the search committee), began his response with "If you think about this a little, you'll see...." Nothing like implying that your potential future employer hasn't considered his question.

Now, though, I've got a new favorite example. From Lubos Motl's well known blog:

(UPDATE: Lubos has removed the page in question, so the link is now broken.)
(UPDATE II: Lubos has put the page back, re-edited, but the new version still conveys his clear view that only high energy theorists, and specifically string theorists, are actually doing science - the rest of us are just wankers, apparently.)

Sorry to say but this is the last well-known physics blog on this planet; all others blogs that claim to have something to do with science are just politically correct tools for crackpots to make their deep misunderstandings of the basics of modern physics ever more powerful and legitimized, and to destroy physics as such at a finite timescale.

Oooooookay. So, everyone else is a complete idiot. Got it. Might as well pack up my computer and quit now.

Recently on cond-mat

Here are a couple of recent preprints that caught my eye. I'm going to try to get back to chronicling these weekly, if I can find the self-discipline....

cond-mat/0606430 - Streed et al., Continuous and pulsed Quantum Zeno Effect
This experiment is really an atomic physics experiment, but it is on cond-mat, and the physics is very cool. The Quantum Zeno Effect gets its name from Zeno's Paradox: in order to get from point A to point B, a person would first have to get half-way; however, to get to the midpoint between A & B, a person would first have to get half-way to that spot, and so on. Thus, noone can ever get anywhere. While the solution to this apparent paradox lies in the idea of rates and limits (at a given instant, there is something called the velocity that is the rate of change of distance per unit time), one can set up a quantum case where a system really never does get from state A to state B. This is a result of the basic postulates of quantum mechanics: after a measurement of some observable, the system is left in an eigenstate of that observable. If the same observable is measured again before the system has had a chance to evolve (via the Schroedinger equation and whatever the Hamiltonian is), the system will still be in that same eigenstate that was just found. So, if one keeps measuring the system continuously, the state of the system can't evolve. The act of continuous measurement locks the system in that one eigenstate. Ketterle's group at MIT have managed to implement a version of this using a Bose-Einstein condensate of rubidium atoms. Very neat.

cond-mat/0606375 - Reich et al., Observation of magnetism in thin gold films
This paper is already out as an Applied Physics Letter. The authors report sensitive magnetic susceptibility measurements on thin Au films, and find that, depending greatly on substrate and preparation, it is possible for those films to be significantly paramagnetic. This is a bit weird, since Au in bulk is diamagnetic. Of course, there have been reports of weird magnetism in nanostructured Au before, including ferromagnetism in Au clusters and whopping big magnetic effects in the presence of self-assembled monolayers of molecules. All of these effects have been challenging for folks to reproduce and confirm, in part because it really does seem like every little detail about sample prep and interfaces matters. It's always interesting to see how even things that seem like they should be well understood can be rich and complex. My personal theory on these effects is that they involve orbital moments in the Au caused by interfacial charge transfer and the strong spin-orbit scattering in Au. Some theorists seem to have the same idea.

Amazingly inappropriate ad from a vendor

Wow. Late this afternoon I got an email advertisement from an equipment vendor that was astonishingly over the line of propriety. The company makes plasma tools for processing semiconductors, and they were advertising their upcoming exhibit at Semicon West, the big semiconductor trade show. One of their pieces of equipment is a tool that uses an oxygen plasma to strip away photoresist residue. The email ad included an image of this tool, and a picture of a (apparently supposedly hot) woman with a come-hither look, and big letters saying "I'll strip for you." I'm hardly a zealot of political correctness, but this was so unprofessional that my jaw dropped. This will not result in increased sales. At most companies something like that would be grounds for a harassment complaint.

UPDATE: here is the ad in question, with the vendor blocked out....

Curse you, rotavirus!

Right now I'm the only member of my family not battling some nasty stomach bug. You know it's bad when your spouse calls you to ask you to pick the recovering younger child up at school, because she and the older child are too ill to get in the car.

Observations about NSF panels

I just returned from an NSF review panel. For those of you that don't know, the NSF peer-reviews all grant proposals, and many programs have a panel review system: an NSF program officer will email you or call you and ask if you are available on such-and-such a date for a panel. If you're willing to do it, you say "yes", and then you're given electronic access to about 8 proposals to review. You do your reviews at your leisure over the next few weeks and upload them via the impressively good web-based system, Fastlane. Then you go to Washington (really Ballston, VA) to NSF headquarters at the appointed time, and sit down in a room with about 10 other reviewers plus the program officer. Everyone has a laptop in front of them, and now you can see each other's reviews. You go through all the proposals (usually about 30 for the whole panel), discuss and compare notes, and in the end write up panel summaries of the reviews that eventually get sent to the proposal writers (PIs, or principal investigators). Typically the proposals are grouped into three categories: "highly recommended" (will actually get funded), "recommended" (on the edge, and may get lucky if there's enough money available), and "not recommended" (no chance). These days the yield of "highly recommended" is 5-15% at NSF, depending on the program. The government pays your travel, and you get a nominal stipend that covers hotel and meals.

A few observations:

• The main reason to do this is one of citizenship: you can really see the process work, learn how to improve your own proposals, and reassure yourself that the people reviewing the grants have a clue.
• Why are there never people from top 15 schools at these panels? Are they really only involved in things like site visits for major center proposals? Seriously, I've never seen someone from any Ivy League school, any of the UC schools, MIT, CalTech, Stanford, Illinois, etc. on one of these things. Are they really all that much busier than me?
• It's painful when someone is on a panel that is not technologically literate enough to handle the web-based system.
• It's equally painful when someone bails at the last minute, doesn't review their share, and doesn't show up.
• This is still the best system around. Scary.

To write, or not to write

I've been talking with a major publishing house about writing a textbook based on my two-semester course sequence, Nanostructures and Nanotechnology I and II. I've been teaching these classes for the last several years, and they've been very successful. The editor has sent out a detailed outline of my ideas, and the feedback from reviewers has been very positive. That's nice and validating, but I remain pretty conflicted about doing this. I know a few things:

• Every one of my research-active faculty colleagues here looks at me like I'm absolutely stark raving bonkers for even considering this - I should be spending all my resources on my research.
• Right now, there is no text for this sort of thing at this level. There is real potential for a transformative effect if the book is good. If I wait 5 years, someone else will write the book instead of me.
• However long I think this will take, it will take longer.
• It would be very nice to feel like I'm having an educational impact on more than 20 students a year.
• I'm unlikely to get any support in this (time off from teaching, etc.) from my institution.
• I have it on good authority that the editor in question is very good, and that this publisher is generally as pleasurable to deal with as any.

So. What to do. Any comments from out there?

This week in cond-mat

Two preprints that caught my eye this week:

cond-mat/0604528 - Elimination of the supersolid state through crystal annealing, Rittner et al.
This paper is the work of John Reppy's group at Cornell, and is part of a large effort going on by a number of people to verify or refute the observations of Moses Chan's group - that there's a "supersolid" state of helium (4He) under high pressure (tens of bars) and low temperatures (below 1 K). A supersolid is a solid that exhibits "nonclassical rotational inertia". Put another way, in a superfluid, the atoms in the system form a kind of condensate - a macroscopic quantum phase where all the atoms behave cooperatively. If the atoms are weakly interacting bosons, the system can be described as a Bose-Einstein condensate. In a supesolid, the vacancies in the crystal lattice are thought to undergo some kind of condensation into a single quantum phase. This new paper reproduces the results of Chan et al., and finds that the supersolid behavior in 4He crystals can be eliminated entirely by annealing the crystals near their melting point. It would appear that the disorder responsible for the supersolidity can be removed by annealing. Nice paper.


cond-mat/0605739 - Landau level spectroscopy of ultrathin graphite layers, Sadowski et al.
This paper shows some beautiful cyclotron resonance data taken on graphene sheets as a function of carrier density. As I've mentioned before, graphene is a very funky model system, in which the electrons and holes act just like (apparently) massless Dirac fermions, because of the peculiarities of the graphene band structure. This work is very pretty, and is a cool example of an experiment that, in some ways, is analogous to electron-positron pair production (!). I'm a big fan of solid state systems that are models of more general physics.

Fraud follow-up

I just received the following email from Phys Rev Letters:

Dear Dr. Natelson,

We are in the process of considering the issues you raise about the
Letter by XXXXX et al.  Such consideration often takes a substantial
amount of time.  Fortunately, in the present case, in which the paper
at issue was published six years ago, there does not appear to be
cause for time pressure.  We will apprise you of our conclusion when
we reach it.


Sincerely,


Reinhardt B. Schuhmann
Editor
Physical Review Letters

Well, I guess we'll see what happens. It'll be interesting to see if anything comes of this. I'm quite sure there's something fishy about the particular paper, but it may be very hard to ever prove.

Possible fraud....

In the course of serving on a committee for a graduate oral presentation, I noticed something very strange looking in a Phys Rev Letter from a few years ago. While unlikely to be seen in a casual glance at the printed version of the journal, it was very striking when the figures were blown up to 4' on a side by a digital projector. Basically, it looks like someone used what I shall delicately term the "Photoshop operator" to massage their data. This paper has been cited 65 times since its publication, and has been milked heavily by its authors.

So, what is the right course of action? I've got no actual proof of fraud, just a very suspicious figure. I've now emailed the editors at PRL twice about this, and received no response from any human being - just the form letter generated by their mail system. Since this is circumstantial, I'm certainly not going to accuse anyone publicly. Next I'm going to call PRL on the phone. Updates as events warrant.