Wide-stopband aperiodic phononic filters

Rostem, Karwan; Chuss, David T.; Denis, Kevin; Wollack, Edward J.

doi:10.1088/0022-3727/49/25/255301

Cited by 14 publications

(21 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…13,19 v. The ratio α/β is typically in the range 10 − 200. 13,[20][21][22] vi. The measured I c (Φ) shows a mostly Fraunhoferlike dependence, although the dependence is not exact.…”

Section: Introductionmentioning

confidence: 99%

Modelling proximity effects in transition edge sensors to investigate the influence of lateral metal structures

Harwin¹,

Goldie²,

Withington³

2017

Supercond. Sci. Technol.

View full text Add to dashboard Cite

The bilayers of Transition Edge Sensors (TESs) are often modified with additional normal-metal features such as bars or dots. Previous device measurements suggest that these features improve performance, reducing electrical noise and altering response times. However, there is currently no numerical model to predict and quantify these effects. Here we extend existing techniques based on Usadel's equations to describe TESs with normal-metal features. We show their influence on the principal TES characteristics, such as the small-signal electrothermal parameters α and β and the superconducting transition temperature Tc. Additionally, we examine the effects of an applied magnetic field on the device performance. Our model predicts a decrease in Tc, α and β as the number of lateral metal structures is increased. We also obtain a relationship between the length L of a TES and its critical temperature, Tc ∝ L −0.7 for a bilayer with normal-metal bars. We predict a periodic magnetic flux dependence of α, β and Ic. Our results demonstrate good agreement with published experimental data, which also show the reduction of α, β and Tc with increasing number of bars. The observed Fraunhofer dependence of critical current on magnetic flux is also anticipated by our model. The success of this model in predicting the effects of additional structures suggests that in the future numerical methods can be used to better inform the design of TESs, prior to device processing.

show abstract

“…13,19 v. The ratio α/β is typically in the range 10 − 200. 13,[20][21][22] vi. The measured I c (Φ) shows a mostly Fraunhoferlike dependence, although the dependence is not exact.…”

Section: Introductionmentioning

confidence: 99%

Modelling proximity effects in transition edge sensors to investigate the influence of lateral metal structures

Harwin¹,

Goldie²,

Withington³

2017

Supercond. Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…The rejection level is typically 10 3 with 3 units cells, and greater than 10 6 with 6 or more unit cells. 4,9 Figure 5 shows that χ reaches an asymptote with r bg , reflecting the finite number of ∼ 2∆ phonons in the superconductor that are prevented from flowing to the thermal bath due to the PnC bandgap.…”

Section: Resultsmentioning

confidence: 99%

Enhanced quasiparticle lifetime in a superconductor by selective blocking of recombination phonons with a phononic crystal

2018

View full text Add to dashboard Cite

When quasiparticles in a BCS superconductor recombine into Cooper pairs, phonons are emitted within a narrow band of energies above the pairing energy at 2∆. We show that a phonon bandgap restricting the escape of recombination phonons from a superconductor can increase the quasiparticle recombination lifetime by more than an order of magnitude. A phonon bandgap can be realized and matched to the recombination energy with a phononic crystal, a periodically-patterned dielectric membrane. We discuss in detail the non-equilibrium quasiparticle and phonon distributions that arise in a superconductor due to a phonon bandgap and a pair-breaking photon signal. Although intrinsically a non-equilibrium effect, the lifetime enhancement in the small-signal regime is remarkably similar to an estimate from an equilibrium formulation. The equilibrium estimate closely follows exp(Ω bg /kBT b ), where Ω bg is the phonon bandgap energy bandwidth above 2∆, and T b is the phonon bath temperature of the coupled electron-phonon system. We discuss the impact of a phononic bandgap on the performance of a superconducting circuit element, and propose a microwave resonator to measure the enhancement in the quasiparticle lifetime. arXiv:1805.06991v2 [cond-mat.supr-con]

show abstract

“…66,68,69 "Phononic filter bolometers" use nanomachined legs to generate coherent phonon scattering that suppresses propagated phonon modes to below the quantum limit. 34,[68][69][70] Like ballistic leg bolometers, phononic filter bolometers promise short legs that enable high array filling fractions but with the additional advantage of reduced thermal conductivity relative to ballistic leg designs. Theoretical work by Rostem et al 68 indicates that a factor of 5 improvement over the quantum limit is possible with phononic filter legs that are just 10 μm long and are machinable using known techniques.…”

Section: Thermal Isolation Techniquesmentioning

confidence: 99%

Transition-edge sensor detectors for the Origins Space Telescope

Nagler

Sadleir

Wollack

2021

J. Astron. Telesc. Instrum. Syst.

View full text Add to dashboard Cite

The Origins Space Telescope is one of four flagship missions under study for the 2020 Astrophysics Decadal Survey. With a 5.9-m cold (4.5 K) telescope deployed from space, Origins promises unprecedented sensitivity in the near-, mid-, and far-infrared from 2.8 to 588 μm. This mandates the use of ultrasensitive and stable detectors in all of the Origins instruments. At the present, no known detectors can meet Origins' stability requirements in the near-to mid-infrared or its sensitivity requirements in the far-infrared. We discuss the applicability of transition-edge sensors, as both calorimeters and bolometers, to meet these requirements, and lay out a path toward improving the present state-of-the-art. © The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

show abstract

Wide-stopband aperiodic phononic filters

Cited by 14 publications

References 22 publications

Modelling proximity effects in transition edge sensors to investigate the influence of lateral metal structures

Modelling proximity effects in transition edge sensors to investigate the influence of lateral metal structures

Enhanced quasiparticle lifetime in a superconductor by selective blocking of recombination phonons with a phononic crystal

Transition-edge sensor detectors for the Origins Space Telescope

Contact Info

Product

Resources

About