Abstract
We carry out a quantum analysis of a dc superconducting quantum interference device (SQUID) mechanical displacement detector, comprising a SQUID with mechanically compliant loop segment, which is embedded in a microwave transmission line resonator. The SQUID is approximated as a nonlinear current-dependent inductance, inducing an external flux tunable nonlinear Duffing self-interaction term in the microwave resonator mode equation. Motion of the compliant SQUID loop segment is transduced inductively through changes in the external flux threading SQUID loop, giving a ponderomotive radiation pressure-type coupling between the microwave and mechanical resonator modes. Expressions are derived for the detector signal response and noise, and it is found that a soft-spring Duffing self-interaction enables a closer approach to the displacement detection standard quantum limit, as well as cooling closer to the ground state.
| Original language | English |
|---|---|
| Article number | 104516 |
| Journal | Physical Review B - Condensed Matter and Materials Physics |
| Volume | 78 |
| Issue number | 10 |
| DOIs | |
| Publication status | Published - 2008 Sep 17 |
| Externally published | Yes |
Fingerprint
ASJC Scopus subject areas
- Condensed Matter Physics
- Electronic, Optical and Magnetic Materials
Cite this
Quantum analysis of a nonlinear microwave cavity-embedded dc SQUID displacement detector. / Nation, Paul; Blencowe, M. P.; Buks, E.
In: Physical Review B - Condensed Matter and Materials Physics, Vol. 78, No. 10, 104516, 17.09.2008.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Quantum analysis of a nonlinear microwave cavity-embedded dc SQUID displacement detector
AU - Nation, Paul
AU - Blencowe, M. P.
AU - Buks, E.
PY - 2008/9/17
Y1 - 2008/9/17
N2 - We carry out a quantum analysis of a dc superconducting quantum interference device (SQUID) mechanical displacement detector, comprising a SQUID with mechanically compliant loop segment, which is embedded in a microwave transmission line resonator. The SQUID is approximated as a nonlinear current-dependent inductance, inducing an external flux tunable nonlinear Duffing self-interaction term in the microwave resonator mode equation. Motion of the compliant SQUID loop segment is transduced inductively through changes in the external flux threading SQUID loop, giving a ponderomotive radiation pressure-type coupling between the microwave and mechanical resonator modes. Expressions are derived for the detector signal response and noise, and it is found that a soft-spring Duffing self-interaction enables a closer approach to the displacement detection standard quantum limit, as well as cooling closer to the ground state.
AB - We carry out a quantum analysis of a dc superconducting quantum interference device (SQUID) mechanical displacement detector, comprising a SQUID with mechanically compliant loop segment, which is embedded in a microwave transmission line resonator. The SQUID is approximated as a nonlinear current-dependent inductance, inducing an external flux tunable nonlinear Duffing self-interaction term in the microwave resonator mode equation. Motion of the compliant SQUID loop segment is transduced inductively through changes in the external flux threading SQUID loop, giving a ponderomotive radiation pressure-type coupling between the microwave and mechanical resonator modes. Expressions are derived for the detector signal response and noise, and it is found that a soft-spring Duffing self-interaction enables a closer approach to the displacement detection standard quantum limit, as well as cooling closer to the ground state.
UR - http://www.scopus.com/inward/record.url?scp=52949139467&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=52949139467&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.78.104516
DO - 10.1103/PhysRevB.78.104516
M3 - Article
VL - 78
JO - Physical Review B-Condensed Matter
JF - Physical Review B-Condensed Matter
SN - 1098-0121
IS - 10
M1 - 104516
ER -