Research Interests

Low Temperature Physics and Critical Phenomena. Transport phenomena. Nonlinear Science. Statistical Physics.

I am a low-temperature physicist and an experimentalist who is interested in developing measurement apparatus that performs well beyond the current limitations of commercially available instrumentation.  More specifically, I have been studying the self organized state near the superfluid transition in liquid helium-4, which is an example of how fascinating complexity results from an otherwise very simple physical system when it is driven away from equilibrium.  For more information on this, please see the Phys. Rev. Lett. by Moeur et al., 1998.  This leads to an anisotropic temperature-entropy wave that exists on this SOC state, and more information on this may be found in the publication by Chatto et al., 2007.  We have also observed the departure from linear response in heat diffusion near the superfluid transition that was predicted by field theory, and that report is in the Phys. Rev. Lett. By P. Day et al., 1998.

We have developed a new class of paramagnetic Susceptibility thermometry that provides unprecedented stability and low levels of noise, and this device has been used in the design of an ultra-stable temperature standard that is predicted to be more stable than the cooling rate of the cosmic background radiation.  For more details, please see the papers by B. Klemme et al, R. Nelson et al., and by Green, Sergatskov, and Duncan. This measurement technology has been incorporated into the design of a fundamental physics mission to study the dynamics of the superfluid transition in space, where these fascinating phenomena are no longer masked by the earth's gravitational acceleration.  For more information on this experiment, and more generally on critical phenomena experiments in space, please see the Rev. Mod. Phys. review by Barmatz et al., and in many of the other papers below. 

In addition to my extensive administrative duties, I am currently chairing the National Academy of Sciences' Panel on Fundamental Physics in Space, which is part of the Decadal Survey that has been mandated by Congress. I have also taken an interest in the excess heat reports in deuterated palladium that have recently been published by the Kitamura Group in Kobe, Japan, by the McKubre Group at SRI, by the Navy SPAWAR Laboratory, by Energetic Technologies, Inc., and by many others.  These empirical observations are now reproducible, but they are not well understood theoretically.  These observations demonstrate that our understanding of condensed matter physics is incomplete, as I suspect it will always be.  These confounding experimental results challenge us to learn more.

1. "Singularity in the Kapitza Resistance between Gold and Superfluid 4He" with Guenter Ahlers and Victor Steinberg, Phys. Rev. Lett. 58, 377 (1987).

2. "Nonlinearity in the Kapitza Resistance Between Gold and Superfluid 4He Near Tl", with G. Ahlers, Jpn. J. Appl. Phys. 26-3, 363 (1987).

3. "Depression of the Superfluid Transition in 4He by a Heat Current" with Guenter Ahlers and Victor Steinberg, Phys. Rev. Lett. 60, 1522 (1988).

4. "Finite-Size Effects on the Thermal Conductivity of 4He Near the Superfluid Transition" with Guenter Ahlers, Phys. Rev. Lett. 61, 846 (1988).

5. "Recent Experiments near the Superfluid Transition in 4He" with Guenter Ahlers, in Frontiers of Physics, Proceedings of the Landau Memorial Conference,  E. Gotsman, Y. Ne'eman, and A. Voronel (eds.), p.219 (Oxford : Pergamon Press 1990).

6. "Thermal effects on the Josephson series-array voltage standard", Physica B 165-166, 101 (1990).

7. "Singularity and Nonlinearity in the Kapitza Resistance Between Gold and Superfluid 4He", with G. Ahlers, Phys. Rev. B 43, 7707 (1991).

8. "Using a New Generation of Multimeters to Measure the Quantized Resistance" with M.E. Cage, D.Y. Yu, B.M. Jeckelmann, and R.L. Steiner, IEEE Transactions on Instruments and Measurements 40, 262 (1991).

9. "A Refrigerated Dewar for the Josephson Array Voltage Calibration System" IEEE Transactions on Instrumentation and Measurement 40, 326 (1991).

10. "Measurement accuracy of macroscopic quantum circuits with rf-biased Josephson junction arrays" with D. H. Dunlap, Superconductor Science and Technology 4, 413 (1991).

11. "Proposed differential frequency readout system by hysteretic Josephson junctions" with L. Z. Wang, Phys. Rev. A 46, 3617 (1992).

12. "Superconducting Instrumentation for Precision Measurement and Control", in Superconducting Devices and Their Applications, page 446, H. Koch and H. Lubbig, editors (Springer-Verlag, Berlin, 1992).

13. "Fundamental Measurement Accuracy of RF-Biased Josephson Device Comparisons" with D. H. Dunlap, J. Appl. Phys. 71, 6177 (1992).

14. "A Superfluid-Transition Fixed-Point Temperature-Reference" with G. Ahlers, in Temperature : Its Control and Measurement in Science and Industry, Volume 6, page 243, J. F. Schooley, editor (American Institute of Physics Press, New York, 1992).

15. "A frequency to voltage converter based on Bloch oscillations in a capacitively-coupled GaAs-GaAlAs quantum well" with D.Dunlap, V.Kovanis, and J.Simmons, Phys. Rev.B 48, 7975 (1993).

16. "Quantitative Method for Measuring Heat Flux Emitted from a Cryogenic Object", U.S. Patent No. 5,193,909, issued March 16, 1993.

17. "Dynamic measurements near the lambda-point in a low-gravity simulator on the ground" with U.E. Israelsson, D.M. Strayer, T.C.P. Chui, and M. Larson, Physica B 194-196, 593 (1994).

22. "Observation of Self-Organized Criticality Near the Superfluid Transition in 4He", with W.A. Moeur, P.K. Day, F-C. Liu, S.T.P. Boyd, and M.J. Adriaans, Phys. Rev. Lett. 78, 2421 (1997).

23. "Large Enhancement of Boron Carbide's Seebeck Coefficients through Vibrational Softening", with T. L. Aselage, D. Emin, and S. S. McCready, Phys. Rev. Lett. 81, 2316 (1998).

24. "Breakdown of Fourier's Law near the Superfluid Transition in 4He", with P. K. Day, W. A. Moeur, S. McCready, D. Sergatskov, and F-C. Liu, Phys. Rev. Lett. 81, 2474 (1998).

25. "Gravitational Effects on Nonlinear Heat Transport near the Superfluid Transition in 4He", with P. K. Day, S. McCready W. A. Moeur, F-C. Liu, and D. Sergatskov, J. Low Temp. Phys. 113, 861 (1998).

26. "PdMn and PdFe:  New Materials for Temperature Measurement Near 2K", with B. Klemme, M.J. Adriaans, P.K. Day, D.A. Sergatskov, and T.L. Aselage, J. Low Temp. Phys. 116, 133 (1999).

27. "Onset of superfluidity far from equilibrium: dynamical effects on the correlation length", with D. Sergatskov, S. Boyd, T. McCarson, A. Babkin, P. Day, and D. Elliott, Physica B 280, 45 (2000).

28. "Dynamic and Gravitational Effects on the Correlation Volume: Experimental Methods" with D.A. Sergatskov, S.T.P. Boyd, S.S. McCready, T.D. McCarson, A.V. Babkin, P.K. Day, F-C.

Liu, and D. Elliott, J. Low Temp. Phys. 119, 265 (2000).

29. Science Requirements Document for Critical Dynamics in Microgravity, JPL Document Number D-18698, May 31, 2000.

30. "Gravitational alignment in ground-based measurements to support Critical Dynamics in Microgravity" with Sven Mueller, T. D. McCarson, and D. A. Sergatskov, AIP Conference Proceedings  504, 701 (2000).

31. "The CQ Experiment", with T.C.P. Chui, A.H Harter, R.A.M. Lee, A. Chatto, P.K. Day, and D.L. Goodstein, American Institute of Aeronautics and Astronautics, AIAA 2001-4964 (2001).

32. "Critical Dynamics in Microgravity - Flight prototype and planned orbital measurements", with D. Sergatskov, S. Boyd, A. Babkin, T. McCarson and P. Day, American Institute of Aeronautics and Astronautics AIAA-2001-4936 (2001).

33. "Sampled DC technique for high precision resistance measurements" with  P. R. Williamson, J. A. Lipa, and D. A. Sergatskov, American Institute of Aeronautics and Astronautics AIAA-2001-4937 (2001).

34. "Numerical Analysis of a Cryogenic Bolometer for Space Radiation Measurement" with S.T.P. Boyd, W.A. Holmes, and P.R. Williamson, American Institute of Aeronautics and Astronautics AIAA-2001-4969 (2001).

35. "New Measurement Technology for DYNAMX, and for  Future Fundamental Physics Missions in Space" with D. A. Sergatskov, A. V. Babkin, S.T.P. Boyd , R. C. Nelson, P. K. Day, J. Dooley, and D. Elliott, FP-1067, Proc. 2nd Pan Pacific Basin Workshop on Microgravity Science (2001).

36. "The CQ Experiment:  Enhanced Heat Capacity of Superfluid Helium in a Heat Flux", with D. L. Goodstein, A. W. Harter, R. A. M. Lee, A. Chatto, T. C. P. Chui, and P. Day, FP-1025, Proc. 2nd Pan Pacific Basin Workshop on Microgravity Science (2001).

37. "New Paramagnetic Susceptibility Thermometers for Fundamental Physics Measurements" with D. A. Sergatskov, P. K. Day, A. V. Babkin, R. C. Nelson, T. D. McCarson, and S.T.P. Boyd, in Temperature : Its Control and Measurement in Science and Industry, 7, 1009, Dean C. Ripple, editor (American Institute of Physics Press, New York, 2002).

38. "Self-Organized Heat Transport near the Superfluid Transition in 4He" with D.L. Goodstein, A.V. Babkin, and D.A. Sergatskov, J. Low Temp. Phys. 126, 1529 (2002).

39. Proceedings of the 2002 Conference on Unified Science and Technology for Reducing Biological Threats and Countering Terrorism (BTR 2002), R. V. Duncan, Chair, University of New Mexico

40. "The Magnetic Properties of Sputtered Pd1-xMnx Films for Thermometry and Bolometry", with R.C. Nelson and D.A. Sergatskov,  J. Low Temp. Phys. 127, 173 (2002).

41. "The CQ Experiment: Enhanced Heat Capacity of Superfluid Helium in a Heat Flux", with R. A. M. Lee, A. W. Harter, A. Chatto, T. C. P. Chui, P. K. Day and D. L. Goodstein, Paper-2.0103, 2002 IEEE Aerospace Conference, 1-31 (2002).

42. "Ultrasound Imaging of Breast Tissue" with N. Duric, P. Littrup, E. Holsapple, A. Babkin, A. Kalinin, A. Pevzner, and A. Tokarev, Proceedings of the SPIE: Medical Imaging 2003; San Diego, California; Feb. 21-26, 2003. Ultrasonic Imaging and Signal Processing - Paper 5035-4.

43. "New Propagating Mode Near the Superfluid Transition in 4He", with D.A. Sergatskov, A.V. Babkin, R.A.M. Lee, and S.T.P. Boyd, Physica B 329 - 333, 208 (2003).

44. "New Paramagnetic Susceptibility Thermometers for Fundamental Physics Measurements" with D.A. Sergatskov, P.K. Day, A.V. Babkin, R.C. Nelson, T.D. McCarson, and S.T.P. Boyd, AIP Conference Procedings 684, 1009 (2003).

45. Proceedings of the 2003 Conference on Unified Science and Technology for Reducing Biological Threats and Countering Terrorism (BTR 2003), R. V. Duncan, Chair, University of New Mexico

46. "'Heat from Above' heat capacity measurements in liquid 4He", with R.A.M. Lee, A. Chatto, D.A. Sergatskov, A.V. Babkin, S.T.P. Boyd, A.M. Churilov, T.D. McCarson, T.C.P. Chui, P.K. Day, and D.L. Goodstein,  J. Low Temp. Phys. 134, 495 (2004).

47. "Preface to the Proceedings of QFS 2003" with S.T.P. Boyd and D. L. Goodstein,  J. Low Temp. Phys. 134, 1 (2004); "Welcome Address to QFS 2003, delivered by Louis Caldera, President of UNM",  J. Low Temp. Phys. 134, 17 (2004).

48. "Experiments in 4He Heated From Above, Very Near the Lambda Point", with D.A. Sergatskov, A.V. Babkin, S.T.P. Boyd, and R.A.M. Lee, J. Low Temp. Phys. 134, 517 (2004).

49. "Experiments in Fundamental Physics Scheduled and in Development for the ISS" with C. Lammerzahl, G. Ahlers, N. Ashby, M. Barmatz, P. Beirmann, H. Dittus, V. Dohm, K. Gibble, J. Lipa, N. Lockerbie, N. Mulders, and C. Salomon, General Relativity and Gravitation 36, 615 (2004).

50. "Fundamental Physics:  Long-range quantum order, interactions, and phase transitions" (Preface), Advances in Space Research, Elsevier, (2004).

51. Proceedings of the 2004 Conference on Unified Science and Technology for Reducing Biological Threats and Countering Terrorism (BTR 2004), R. V. Duncan, Chair, University of New Mexico.

52. "Demonstration of an Ultra-Stable Temperature Platform" with C. J. Green and D. A. Sergatskov,  J. Low Temp. Phys. 138, 871 (2005).

53. "Adaptive Optimal PI Controller for Use in Precision Low-Temperature Experiments" with Jinyang Liu and D. A. Sergatskov, J. Low Temp. Phys. 138, 905 (2005).

54. "Dynamic Simulation of the Superfluid / Normal Fluid Interface Motion in 4He" with Z. Xie, N. C. Menicucci, S.T.P. Boyd, and D. A. Sergatskov, J. Low Temp. Phys. 138, 79 (2005).

55. Proceedings of the 2005 Conference on Unified Science and Technology for Reducing Biological Threats and Countering Terrorism (BTR 2005), R. V. Duncan, Chair, University of New Mexico.

56. "CW Measurements of the Upward-Going Temperature Wave in the 4He Self-Organized Critical State" with S.T.P. Boyd and D.A. Sergatskov, AIP Conference Proceedings 850, 135 (ISBN 0-7354-0347-3; 2006).

57. "Effect of Inhomogeneous Heat Flow on the Enhancement of the Heat Capacity in He-II by Counterflow near Tl", with S.T.P. Boyd, A. Chatto, R.A.M. Lee, and D. Goodstein, AIP Conference Proceedings 850, 133 (ISBN 0-7354-0347-3; 2006).

58. "Measurement of the SOC State Specific Heat in 4He" with A.R. Chatto, R.A.M. Lee, P.K. Day and D.L. Goodstein, AIP Conference Proceedings 850, 137 (ISBN 0-7354-0347-3; 2006).

59. "Magnetic Properties of Pd(96%)Mn(4%) Films for High Resolution Thermometry" with R. C. Nelson, C. Green, and D.A. Sergatskov, AIP Conference Proceedings 850, 1123 (ISBN 0-7354-0347-3; 2006).

60. "Experiments on the Self-Organized Critical State of 4He" with A. Chatto, R.A.M. Lee, and D. Goodstein, J. Low Temp. Phys. 148, 519 (2007).

61. "Noise Immunity of High-Precision Low-Temperature Experiments" with J. Liu and D.A. Sergatskov, J. Low Temp. Phys. 148, 921 (2007).

62. "Critical phenomena in microgravity:  Past, present, and future", with Martin Barmatz, Inseob Hahn, and John Lipa, Reviews of Modern Physics, 79, pp. 1-52 (January - March, 2007).