Abstract
Several technologies are now being considered for modulating the polarization in various B-mode instruments, including rotating quasioptical half-wave plates in front of the focal plane array, rotating waveguide half-wave plates and Faraday rotators. It is not at all clear that any of these techniques is feasible without heavy penalty in cost or performance. A potentially much more efficient method is to use a pseudo-correlation polarimeter in conjunction with a planar circuit phase switch. We investigate three different devices for use as mm-wave switches, SIS tunnel junctions, capacitively coupled super-conducting nanostrips and RF MEMS. The SIS tunnel junction switches operate by switching between two different bias voltages, while the nanostrip switch operates by changing the impedance of a resonant circuit by driving the nanostrip from the superconducting to normal state. In each case the RF signal sees two substantially different complex impedance states, hence could be switched from one transmission line branch to another. In MEMS this is achieved by mechanical movement of one plate of a parallel plate capacitor system. Although RF MEMS have been reported at high microwave and low mm-wave frequencies, in this work we have investigated cryogenic MEMS for operation at high mm-wave frequencies (225 GHz) using superconducting transmission lines. We present and compare designs and simulations of the performance of phase switches based on all three switching technologies, as well as preliminary experimental results for each of the switches. Finally we also present designs of phase shift circuits that translates the on/off switching into phase modulation.
| Original language | English (US) |
|---|---|
| Title of host publication | Proceedings of SPIE - The International Society for Optical Engineering |
| Volume | 6275 |
| DOIs | |
| State | Published - 2006 |
| Externally published | Yes |
| Event | Millimeter and Submillimeter Detectors and Instrumentation for Astronomy III - Orlando, FL, United States Duration: May 29 2006 → May 31 2006 |
Other
| Other | Millimeter and Submillimeter Detectors and Instrumentation for Astronomy III |
|---|---|
| Country | United States |
| City | Orlando, FL |
| Period | 5/29/06 → 5/31/06 |
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ASJC Scopus subject areas
- Electrical and Electronic Engineering
- Condensed Matter Physics
Cite this
Investigation of planar switches for large format CMB polarization instruments. / Grimes, Paul K.; Yassin, Ghassan; Kuzmin, Leonid S.; Mauskopf, Philip; Otto, Ernst; Jones, Michael E.; North, Chris E.
Proceedings of SPIE - The International Society for Optical Engineering. Vol. 6275 2006. 627525.Research output: Chapter in Book/Report/Conference proceeding › Conference contribution
}
TY - GEN
T1 - Investigation of planar switches for large format CMB polarization instruments
AU - Grimes, Paul K.
AU - Yassin, Ghassan
AU - Kuzmin, Leonid S.
AU - Mauskopf, Philip
AU - Otto, Ernst
AU - Jones, Michael E.
AU - North, Chris E.
PY - 2006
Y1 - 2006
N2 - Several technologies are now being considered for modulating the polarization in various B-mode instruments, including rotating quasioptical half-wave plates in front of the focal plane array, rotating waveguide half-wave plates and Faraday rotators. It is not at all clear that any of these techniques is feasible without heavy penalty in cost or performance. A potentially much more efficient method is to use a pseudo-correlation polarimeter in conjunction with a planar circuit phase switch. We investigate three different devices for use as mm-wave switches, SIS tunnel junctions, capacitively coupled super-conducting nanostrips and RF MEMS. The SIS tunnel junction switches operate by switching between two different bias voltages, while the nanostrip switch operates by changing the impedance of a resonant circuit by driving the nanostrip from the superconducting to normal state. In each case the RF signal sees two substantially different complex impedance states, hence could be switched from one transmission line branch to another. In MEMS this is achieved by mechanical movement of one plate of a parallel plate capacitor system. Although RF MEMS have been reported at high microwave and low mm-wave frequencies, in this work we have investigated cryogenic MEMS for operation at high mm-wave frequencies (225 GHz) using superconducting transmission lines. We present and compare designs and simulations of the performance of phase switches based on all three switching technologies, as well as preliminary experimental results for each of the switches. Finally we also present designs of phase shift circuits that translates the on/off switching into phase modulation.
AB - Several technologies are now being considered for modulating the polarization in various B-mode instruments, including rotating quasioptical half-wave plates in front of the focal plane array, rotating waveguide half-wave plates and Faraday rotators. It is not at all clear that any of these techniques is feasible without heavy penalty in cost or performance. A potentially much more efficient method is to use a pseudo-correlation polarimeter in conjunction with a planar circuit phase switch. We investigate three different devices for use as mm-wave switches, SIS tunnel junctions, capacitively coupled super-conducting nanostrips and RF MEMS. The SIS tunnel junction switches operate by switching between two different bias voltages, while the nanostrip switch operates by changing the impedance of a resonant circuit by driving the nanostrip from the superconducting to normal state. In each case the RF signal sees two substantially different complex impedance states, hence could be switched from one transmission line branch to another. In MEMS this is achieved by mechanical movement of one plate of a parallel plate capacitor system. Although RF MEMS have been reported at high microwave and low mm-wave frequencies, in this work we have investigated cryogenic MEMS for operation at high mm-wave frequencies (225 GHz) using superconducting transmission lines. We present and compare designs and simulations of the performance of phase switches based on all three switching technologies, as well as preliminary experimental results for each of the switches. Finally we also present designs of phase shift circuits that translates the on/off switching into phase modulation.
UR - http://www.scopus.com/inward/record.url?scp=33749624261&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33749624261&partnerID=8YFLogxK
U2 - 10.1117/12.671151
DO - 10.1117/12.671151
M3 - Conference contribution
AN - SCOPUS:33749624261
SN - 081946340X
SN - 9780819463401
VL - 6275
BT - Proceedings of SPIE - The International Society for Optical Engineering
ER -