Research Interests and Activities

Jonathan Maps

Research Overview

My research interests are in the area of experimental condensed matter physics, including scanned probe microscopy and low-temperature physics. Atomic force microscopy (AFM) is being developed to study mechanical properties of materials on the nanometer scale. Scanning tunneling microscopy has been developed for studies of electronic properties of materials, especially superconductors. The current-voltage characteristics of the tunneling current in an STM provide a spectroscopic tool to study superconductivity.

• More on STM and some images
• A report on some AFM work (pdf)
• Go to the Physics Home Page
• Go to the J. Maps Home Page

Publications

• "Superflow Onset: ⁴He on Grafoil," with R. B. Hallock, in Ordering in Two Dimensions, ed. S. K. Sinha, North-Holland, New York (1980) p. 271.
• "Thermal Conductivity Measurements in Helium Films on a Mylar Substrate," with R. B. Hallock, Proceedings of LT-16, Physica B+C, 107, 399 (1981).
• "Onset of Superfluid Flow in ⁴He Films Adsorbed on Mylar," with R. B. Hallock, Phys. Rev. Lett. 47, 1533 (1981).
• "Thermal Transport on the Superfluid Side of the Kosterlitz- Thouless Transition in ⁴He Films," with R. B. Hallock, Phys. Rev. B26, 3979 (1982).
• "Simultaneous Mass Flow and Third Sound Measurements in ⁴He Films Near the Kosterlitz-Thouless Transition," with R. B. Hallock, Phys. Rev. B28, 4021 (1983).
• "Experimental Study of the Kosterlitz-Thouless Transition in ⁴He Films," with R. B. Hallock, Phys. Rev. B27, 5491 (1983).
• "Third Sound Measurements on ⁴He Films in the Vicinity of the Kosterlitz-Thouless Transition," with R. B. Hallock, in 75th Jubilee Conference on ⁴He, ed. J. G. M. Armitage, World Scientific, Singapore (1983) p. 94.
• "Reactive Evaporation of Chevrel Phase Superconducting Compounds," with R. J. Webb, A. M. Goldman, J. H. Kang, and M. F. Schmidt, IEEE Trans. Magnetics, MAG-21, 835 (1985).
• "Superconductivity of HoMo₆S₈ Thin Films," with J. H.Kang, and A. M. Goldman, Proceedings of the International Conference on Materials and Mechanisms of Superconductivity, Physica 135B, 336 (1985).
• "The Superconducting-Normal Phase Boundary of a Fractal Network in a Magnetic Field," with James M. Gordon, A. M. Goldman, D. Costello, R. Tiberio, and B. Whitehead, Phys. Rev. Lett. 56, 2280 (1986).
• "Superconductivity in the Ferromagnetic Phase of Polycrystalline HoMo₆S₈ Films," with D. D. Berkley, J. H. Kang, and A. M. Goldman, Phys. Rev. B35, 38 (1987).
• "Superconducting Transition in Thin Films of Lead Telluride Doped with Thallium," with J. H. Kang, D. D. Berkley, H. M. Jaeger, A. M. Goldman, and Dale L. Partin, Phys. Rev. B36, 2280 (1987).
• "Critical Magnetic Field Measurements of UBe₁₃ Thin Films," with J. H. Kang, and A. M. Goldman, Proceedings of the 18th International Conference on Low Temperature Physics, Kyoto, Japan, (1987).
• "Critical Fields of UBe₁₃ Films," with J. H. Kang, A. M. Goldman, J. S. Brooks, Z. Fisk, and J. L. Smith in Novel Superconductivity, Proceedings of the International Workshop on Novel Mechanisms of Superconductivity, Berkeley, CA 22-26 June 1987, Plenum New York, NY (1987) p. 215-21.
• "Electron Tunneling into Single Crystals of YBa₂Cu₃O_7-x" with J.C. Wan and A. M. Goldman, Physica C 153-155, 1377 (1988).
• "Preparation of Y₂Ba₄Cu₈O_20-x Thin Films by Thermal Coevaporation," with D. D. Berkley, D. H. Kim, B. R. Johnson, A. M. Goldman, M. L. Mecartney, and K. Beauchamp, Appl. Phys. Lett. 53, 708 (1988).
• "Ozone Processing of MBE Grown YBa₂Cu₃O_7-x Films," with D. D. Berkley, B. R. Johnson, N. Anand, K. M. Beauchamp, L. E. Conroy, A. M. Goldman, K. Mauersberger, M. L. Mecartney, J. Morton, M. Tuominen, and Y-J. Zhang, Proceedings of the Applied Superconductivity Conference, 1988.
• "In-situ Formation of Superconducting YBa₂Cu₃O_7-x Thin Films Using Pure Ozone Vapor Oxidation," with D. D. Berkley, B. R. Johnson, N. Anand, K. M. Beauchamp, L. E. Conroy, A. M. Goldman, K. Mauersberger, M. L. Mecartney, J. Morton, M. Tuominen, and Y-J. Zhang, Appl. Phys. Lett. 53, 1973 (1988).
• "Simple Raster Generator for Use with Scanning Tunneling Microscopes," Rev. Sci. Instrum. 62, 357 (1991).
• "A Computer-based Data Acquisition Laboratory for Undergraduates," Am. J. Phys. 61, 651 (1993).
• "Simple Determination of the Frequency Response of Piezoelectric Tubes," with L. Tao Rev. Sci. Instrum., 64, 1367 (1993).

Grants

"Atomic force microscopy of thermal insulation materials with aerogels,'
NASA, April 2001 - March 2002, $13,646.

"Low temperature scanning tunneling microscopy of superconductors below 1K"
Joseph H. DeFrees Grant of the Research Corporation, July 1989 - September 1993, $32,000.

"Integration of computer-based data acquisition and analysis in an electronics sequence for science majors"
National Science Foundation, June 1989 - November 1991, $30,935.

"Low temperature tunneling microscopy of superconducting materials"
University of Minnesota Graduate School, December 1987 - June 1988, $14,000.

---