High-bandwidth, variable-resistance differential noise thermometry
Abstract
We have developed Johnson noise thermometry applicable to mesoscopic devices with variable source impedance with high bandwidth for fast data acquisition. By implementing differential noise measurement and two-stage impedance matching, we demonstrate noise measurement in the frequency range of 120 MHz–250 MHz with a wide sample resistance range of 30 Ω–100 kΩ tuned by gate voltages and temperature. We employed high-frequency, single-ended low noise amplifiers maintained at a constant cryogenic temperature in order to maintain the desired low noise temperature. We have achieved thermometer calibration with temperature precision up to 650 μK measuring a 200 mK temperature modulation on a 10 K background with 30 s of averaging. Using this differential noise thermometry technique, we measured thermal conductivity on a bilayer graphene sample spanning the metallic and semiconducting regimes in a wide resistance range, and we compared it to the electrical conductivity.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jan 01, 2021
- Source ID
- 10.1063/5.0026488
Entities
People
- Artem V. Talanov
- Jonah Waissman
- Kenji Watanabe
- Philip Kim
- Takashi Taniguchi
Organizations
- Army Research Office
- Core Research for Evolutional Science and Technology
- Harvard University
- Japan Society for the Promotion of Science
- Ministry of Education, Culture, Sports, Science and Technology
- National Institute for Materials Science
- National Science Foundation
- Office of Naval Research