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Published on: August 2, 2019
Bolometer operating at the threshold for circuit quantum electrodynamics
R Kokkoniemi1,2, J-P Girard1, D Hazra1,3
1QCD Labs, QTF Centre of Excellence, Department of Applied Physics, Aalto University, Espoo, Finland.
Researchers developed a novel graphene bolometer for quantum technology. This highly sensitive thermal sensor achieves nanosecond time constants and excellent energy resolution, meeting critical thresholds for circuit quantum electrodynamics applications.
Area of Science:
- Quantum Technology
- Sensor Development
- Materials Science
Background:
- Thermal sensors are vital for applications like gas detection and security.
- Emerging quantum technologies, particularly circuit quantum electrodynamics, require highly sensitive and fast detectors.
- Existing thermal sensors have not met the stringent time constant and energy resolution requirements for circuit quantum electrodynamics.
Purpose of the Study:
- To experimentally demonstrate a bolometer capable of meeting the threshold for circuit quantum electrodynamics.
- To develop a thermal sensor with a time constant of a few hundred nanoseconds and an energy resolution of approximately 10 Planck constants (h).
- To leverage novel materials for enhanced bolometer performance.
Main Methods:
- Utilized a graphene monolayer with extremely low specific heat as the active material for the bolometer.
- Directly measured the noise-equivalent power and thermal time constant on the same device.
- Characterized the calorimetric energy resolution based on experimental data.
Main Results:
- Demonstrated a bolometer operating at the circuit quantum electrodynamics threshold.
- Achieved a noise-equivalent power of 30 zeptowatts per square-root hertz.
- Obtained a thermal time constant of 500 nanoseconds, two orders of magnitude shorter than previous limitations, with a minimum observed time constant of 200 nanoseconds.
- Determined a calorimetric energy resolution of 30 Planck constants (h).
Conclusions:
- The developed graphene bolometer meets the critical performance thresholds for circuit quantum electrodynamics applications.
- The sensor's fast response time and high energy resolution enable integration with superconducting qubits and readout schemes.
- This advancement paves the way for enhanced quantum computing and sensing.
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