1
|
McRae CRH, Wang H, Gao J, Vissers MR, Brecht T, Dunsworth A, Pappas DP, Mutus J. Materials loss measurements using superconducting microwave resonators. Rev Sci Instrum 2020; 91:091101. [PMID: 33003823 DOI: 10.1063/5.0017378] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 08/20/2020] [Indexed: 06/11/2023]
Abstract
The performance of superconducting circuits for quantum computing is limited by materials losses. In particular, coherence times are typically bounded by two-level system (TLS) losses at single photon powers and millikelvin temperatures. The identification of low loss fabrication techniques, materials, and thin film dielectrics is critical to achieving scalable architectures for superconducting quantum computing. Superconducting microwave resonators provide a convenient qubit proxy for assessing performance and studying TLS loss and other mechanisms relevant to superconducting circuits such as non-equilibrium quasiparticles and magnetic flux vortices. In this review article, we provide an overview of considerations for designing accurate resonator experiments to characterize loss, including applicable types of losses, cryogenic setup, device design, and methods for extracting material and interface losses, summarizing techniques that have been evolving for over two decades. Results from measurements of a wide variety of materials and processes are also summarized. Finally, we present recommendations for the reporting of loss data from superconducting microwave resonators to facilitate materials comparisons across the field.
Collapse
Affiliation(s)
- C R H McRae
- Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
| | - H Wang
- Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
| | - J Gao
- Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
| | - M R Vissers
- National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| | - T Brecht
- HRL Laboratories, Malibu, California 90265, USA
| | - A Dunsworth
- Google, Inc., Mountain View, California 94043, USA
| | - D P Pappas
- National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| | - J Mutus
- Boulder Cryogenic Quantum Testbed, University of Colorado, Boulder, Colorado 80309, USA
| |
Collapse
|
2
|
Walker S, Sierra CE, Austermann JE, Beall JA, Becker DT, Dober BJ, Duff SM, Hilton GC, Hubmayr J, Van Lanen JL, McMahon JJ, Simon SM, Ullom JN, Vissers MR. Demonstration of 220/280 GHz Multichroic Feedhorn-Coupled TES Polarimeter. J Low Temp Phys 2020; 199:10.1007/s10909-019-02316-1. [PMID: 33487736 PMCID: PMC7818388 DOI: 10.1007/s10909-019-02316-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 12/16/2019] [Indexed: 06/12/2023]
Abstract
We describe the design and measurement of feedhorn-coupled, transition-edge sensor (TES) polarimeters with two passbands centered at 220 GHz and 280 GHz, intended for observations of the cosmic microwave background. Each pixel couples polarized light in two linear polarizations by use of a planar orthomode transducer and senses power via four TES bolometers, one for each band in each linear polarization. Previous designs of this detector architecture incorporated passbands from 27 to 220 GHz; we now demonstrate this technology at frequencies up to 315 GHz. Observational passbands are defined with an on-chip diplexer, and Fourier-transform-spectrometer measurements are in excellent agreement with simulations. We find coupling from feedhorn to TES bolometer using a cryogenic, temperature-controlled thermal source. We determine the optical efficiency of our device is η = 77% ± 6% (75% ± 5%) for 220 (280) GHz, relative to the designed passband shapes. Lastly, we compare two power-termination schemes commonly used in wide-bandwidth millimeter-wave polarimeters and find equal performance in terms of optical efficiency and passband shape.
Collapse
Affiliation(s)
- S. Walker
- University of Colorado Boulder, Boulder, CO, USA
- National Institute of Standards and Technology, Boulder, CO, USA
| | | | - J. E. Austermann
- National Institute of Standards and Technology, Boulder, CO, USA
| | - J. A. Beall
- National Institute of Standards and Technology, Boulder, CO, USA
| | - D. T. Becker
- University of Colorado Boulder, Boulder, CO, USA
- National Institute of Standards and Technology, Boulder, CO, USA
| | - B. J. Dober
- National Institute of Standards and Technology, Boulder, CO, USA
| | - S. M. Duff
- National Institute of Standards and Technology, Boulder, CO, USA
| | - G. C. Hilton
- National Institute of Standards and Technology, Boulder, CO, USA
| | - J. Hubmayr
- National Institute of Standards and Technology, Boulder, CO, USA
| | - J. L. Van Lanen
- National Institute of Standards and Technology, Boulder, CO, USA
| | | | | | - J. N. Ullom
- University of Colorado Boulder, Boulder, CO, USA
- National Institute of Standards and Technology, Boulder, CO, USA
| | - M. R. Vissers
- National Institute of Standards and Technology, Boulder, CO, USA
| |
Collapse
|
3
|
Austermann JE, Beall JA, Bryan SA, Dober B, Gao J, Hilton G, Hubmayr J, Mauskopf P, McKenney CM, Simon SM, Ullom JN, Vissers MR, Wilson GW. Millimeter-Wave Polarimeters Using Kinetic Inductance Detectors for TolTEC and Beyond. J Low Temp Phys 2018; 193:10.1007/s10909-018-1949-5. [PMID: 34815585 PMCID: PMC8607460 DOI: 10.1007/s10909-018-1949-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 04/30/2018] [Indexed: 06/11/2023]
Abstract
Microwave Kinetic Inductance Detectors (MKIDs) provide a compelling path forward to the large-format polarimeter, imaging, and spectrometer arrays needed for next-generation experiments in millimeter-wave cosmology and astronomy. We describe the development of feedhorn-coupled MKID detectors for the TolTEC millimeter-wave imaging polarimeter being constructed for the 50-meter Large Millimeter Telescope (LMT). Observations with TolTEC are planned to begin in early 2019. TolTEC will comprise ∼7,000 polarization sensitive MKIDs and will represent the first MKID arrays fabricated and deployed on monolithic 150 mm diameter silicon wafers - a critical step towards future large-scale experiments with over 105 detectors. TolTEC will operate in observational bands at 1.1, 1.4, and 2.0 mm and will use dichroic filters to define a physically independent focal plane for each passband, thus allowing the polarimeters to use simple, direct-absorption inductive structures that are impedance matched to incident radiation. This work is part of a larger program at NIST-Boulder to develop MKID-based detector technologies for use over a wide range of photon energies spanning millimeter-waves to X-rays. We present the detailed pixel layout and describe the methods, tools, and flexible design parameters that allow this solution to be optimized for use anywhere in the millimeter and sub-millimeter bands. We also present measurements of prototype devices operating in the 1.1 mm band and compare the observed optical performance to that predicted from models and simulations.
Collapse
Affiliation(s)
- J E Austermann
- Quantum Sensors Group, National Institute of Standards and Technology; Boulder, CO 80305, USA
| | - J A Beall
- Quantum Sensors Group, National Institute of Standards and Technology; Boulder, CO 80305, USA
| | | | - B Dober
- Quantum Sensors Group, National Institute of Standards and Technology; Boulder, CO 80305, USA
| | - J Gao
- Quantum Sensors Group, National Institute of Standards and Technology; Boulder, CO 80305, USA
| | - G Hilton
- Quantum Sensors Group, National Institute of Standards and Technology; Boulder, CO 80305, USA
| | - J Hubmayr
- Quantum Sensors Group, National Institute of Standards and Technology; Boulder, CO 80305, USA
| | | | - C M McKenney
- Quantum Sensors Group, National Institute of Standards and Technology; Boulder, CO 80305, USA
| | - S M Simon
- University of Michigan, Ann Arbor, MI
| | - J N Ullom
- Quantum Sensors Group, National Institute of Standards and Technology; Boulder, CO 80305, USA
| | - M R Vissers
- Quantum Sensors Group, National Institute of Standards and Technology; Boulder, CO 80305, USA
| | - G W Wilson
- University of Massachusetts, Amherst, MA
| |
Collapse
|
4
|
Sanford NA, Blanchard PT, White R, Vissers MR, Diercks DR, Davydov AV, Pappas DP. Laser-assisted atom probe tomography of Ti/TiN films deposited on Si. Micron 2017; 94:53-65. [PMID: 28063337 DOI: 10.1016/j.micron.2016.12.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 12/05/2016] [Accepted: 12/06/2016] [Indexed: 11/20/2022]
Abstract
Laser-assisted atom probe tomography (L-APT) was used to examine superconducting TiN/Ti/TiN trilayer films with nominal respective thicknesses of 5/5/5 (nm). Such materials are of interest for applications that require large arrays of microwave kinetic inductance detectors. The trilayers were deposited on Si substrates by reactive sputtering. Electron energy loss microscopy performed in a scanning transmission electron microscope (STEM/EELS) was used to corroborate the L-APT results and establish the overall thicknesses of the trilayers. Three separate batches were studied where the first (bottom) TiN layer was deposited at 500°C (for all batches) and the subsequent TiN/Ti bilayer was deposited at ambient temperature, 250°C, and 500°C, respectively. L-APT rendered an approximately planar TiN/Si interface by making use of plausible mass-spectral assignments to N31+, SiN1+, and SiO1+. This was necessary since ambiguities associated with the likely simultaneous occurrence of Si1+ and N21+ prevented their use in rendering the TiN/Si interface upon reconstruction. The non-superconducting Ti2N phase was also revealed by L-APT. Neither L-APT nor STEM/EELS rendered sharp Ti/TiN interfaces and the contrast between these layers diminished with increased film deposition temperature. L-APT also revealed that hydrogen was present in varying degrees in all samples including control samples that were composed of single layers of Ti or TiN.
Collapse
Affiliation(s)
- N A Sanford
- National Institute of Standards and Technology, Physical Measurement Laboratory, Division 686, 325 Broadway, Boulder, CO 80305, United States.
| | - P T Blanchard
- National Institute of Standards and Technology, Physical Measurement Laboratory, Division 686, 325 Broadway, Boulder, CO 80305, United States
| | - R White
- National Institute of Standards and Technology, Material Measurement Laboratory, Division 647, 325 Broadway, Boulder, CO 80305, United States
| | - M R Vissers
- National Institute of Standards and Technology, Physical Measurement Laboratory, Division 687, 325 Broadway, Boulder, CO 80305, United States
| | - D R Diercks
- Colorado School of Mines, Department of Metallurgical and Materials Engineering, Golden, CO, 80401, United States
| | - A V Davydov
- National Institute of Standards and Technology, Material Measurement Laboratory, Division 642, 100 Bureau Drive, Gaithersburg, MD 20899, United States
| | - D P Pappas
- National Institute of Standards and Technology, Physical Measurement Laboratory, Division 687, 325 Broadway, Boulder, CO 80305, United States
| |
Collapse
|
5
|
Bockstiegel C, Wang Y, Vissers MR, Wei LF, Chaudhuri S, Hubmayr J, Gao J. A tunable coupler for superconducting microwave resonators using a nonlinear kinetic inductance transmission line. Appl Phys Lett 2016; 108:222604. [PMID: 29332947 PMCID: PMC5761681 DOI: 10.1063/1.4953209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We present a tunable coupler scheme that allows us to tune the coupling strength between a feedline and a superconducting resonator in situ over a wide range. In this scheme, we shunt the feedline with a 50-Ω lumped-element nonlinear transmission line made from a 20 nm NbTiN film. By injecting a DC current, the nonlinear kinetic inductance changes and the effective impedance shunting the resonator periodically varies from a short to an open, which tunes the coupling strength and coupling quality factor Qc . We have demonstrated Qc tuning over a factor of 40, between Qc ~ 5.5 × 104 and Qc ~ 2.3 × 106, for a 4.5 GHz resonator by applying a DC current less than 3.3 mA. Our tunable coupler scheme is easy to implement and may find broad applications in superconducting detector and quantum computing/information experiments.
Collapse
Affiliation(s)
- C. Bockstiegel
- National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| | - Y. Wang
- National Institute of Standards and Technology, Boulder, Colorado 80305, USA
- Quantum Optoelectronics Laboratory, Southwest Jiaotong University, Chengdu, Sichuan 610031, China
| | - M. R. Vissers
- National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| | - L. F. Wei
- Quantum Optoelectronics Laboratory, Southwest Jiaotong University, Chengdu, Sichuan 610031, China
| | - S. Chaudhuri
- Department of Physics, Stanford University, Stanford, California 94305, USA
| | - J. Hubmayr
- National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| | - J. Gao
- National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| |
Collapse
|
6
|
Vissers MR, Erickson RP, Ku HS, Vale L, Wu X, Hilton G, Pappas DP. Low-noise kinetic inductance traveling-wave amplifier using three-wave mixing. Appl Phys Lett 2016; 108:012601. [PMID: 27114615 PMCID: PMC4840414 DOI: 10.1063/1.4937922] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We have fabricated a wide-bandwidth, high dynamic range, low-noise cryogenic amplifier based on a superconducting kinetic inductance traveling-wave device. The device was made from NbTiN and consisted of a long, coplanar waveguide on a silicon chip. By adding a DC current and an RF pump tone we are able to generate parametric amplification using three-wave mixing. The devices exhibit gain of more than 15 dB across an instantaneous bandwidth from 4 to 8 GHz. The total usable gain bandwidth, including both sides of the signal-idler gain region, is more than 6 GHz. The noise referred to the input of the devices approaches the quantum limit, with less than 1 photon excess noise. Compared to similarly constructed four-wave mixing amplifiers, these devices operate with the RF pump at ~20 dB lower power and at frequencies far from the signal. This will permit easier integration into large scale qubit and detector applications.
Collapse
Affiliation(s)
- M. R. Vissers
- National Institute of Standards and Technology, Boulder, CO 80305
| | - R. P. Erickson
- National Institute of Standards and Technology, Boulder, CO 80305
| | - H.-S. Ku
- National Institute of Standards and Technology, Boulder, CO 80305
| | - Leila Vale
- National Institute of Standards and Technology, Boulder, CO 80305
| | - Xian Wu
- National Institute of Standards and Technology, Boulder, CO 80305
| | - G. Hilton
- National Institute of Standards and Technology, Boulder, CO 80305
| | - D. P. Pappas
- National Institute of Standards and Technology, Boulder, CO 80305
| |
Collapse
|
7
|
Erickson RP, Vissers MR, Sandberg M, Jefferts SR, Pappas DP. Frequency comb generation in superconducting resonators. Phys Rev Lett 2014; 113:187002. [PMID: 25396390 DOI: 10.1103/physrevlett.113.187002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Indexed: 06/04/2023]
Abstract
We have generated frequency combs spanning 0.5 to 20 GHz in superconducting λ/2 resonators at T=3 K. Thin films of niobium-titanium nitride enabled this development due to their low loss, high nonlinearity, low frequency dispersion, and high critical temperature. The combs nucleate as sidebands around multiples of the pump frequency. Selection rules for the allowed frequency emission are calculated using perturbation theory, and the measured spectrum is shown to agree with the theory. Sideband spacing is measured to be accurate to 1 part in 10(8). The sidebands coalesce into a continuous comb structure observed to cover at least several frequency octaves.
Collapse
Affiliation(s)
- R P Erickson
- National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| | - M R Vissers
- National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| | - M Sandberg
- National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| | - S R Jefferts
- National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| | - D P Pappas
- National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| |
Collapse
|
8
|
Schroer MD, Kolodrubetz MH, Kindel WF, Sandberg M, Gao J, Vissers MR, Pappas DP, Polkovnikov A, Lehnert KW. Measuring a topological transition in an artificial spin-1/2 system. Phys Rev Lett 2014; 113:050402. [PMID: 25126902 DOI: 10.1103/physrevlett.113.050402] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Indexed: 06/03/2023]
Abstract
We present measurements of a topological property, the Chern number (C_{1}), of a closed manifold in the space of two-level system Hamiltonians, where the two-level system is formed from a superconducting qubit. We manipulate the parameters of the Hamiltonian of the superconducting qubit along paths in the manifold and extract C_{1} from the nonadiabatic response of the qubit. By adjusting the manifold such that a degeneracy in the Hamiltonian passes from inside to outside the manifold, we observe a topological transition C_{1}=1→0. Our measurement of C_{1} is quantized to within 2% on either side of the transition.
Collapse
Affiliation(s)
- M D Schroer
- JILA, National Institute of Standards and Technology and The University of Colorado, Boulder, Colorado 80309, USA
| | - M H Kolodrubetz
- Physics Department, Boston University, Boston, Massachusetts 02215, USA
| | - W F Kindel
- JILA, Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
| | - M Sandberg
- National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| | - J Gao
- National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| | - M R Vissers
- National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| | - D P Pappas
- National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| | | | - K W Lehnert
- JILA, National Institute of Standards and Technology and The University of Colorado, Boulder, Colorado 80309, USA and Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
| |
Collapse
|