Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Applied Physics Letters

Frequency-domain multiplexed readout of transition-edge sensor arrays with a superconducting quantum interference device

Trevor M. Lanting, Hsiao-Mei Cho, John L. Clarke, W. L. Holzapfel, Adrian Tae-Jin Lee, Martin Lueker, P. L. Richards, M. Dobbs, H. G. Spieler, A. Smith

Published Mar 11, 2005• 97 citations
Publisher

Abstract

We demonstrate an eight-channel frequency-domain readout multiplexer for superconducting transition-edge sensors (TESs). Each sensor is biased with a sinusoidal voltage at a unique frequency. The sensor currents are summed and measured with a single superconducting quantum interference device (SQUID) array. The 100-element SQUID array is operated with shunt feedback electronics that have a slew rate of 1.2×107Φ0∕s at 1MHz. The multiplexer readout noise is 6.5pA∕Hz, which is well below the expected sensor noise of 15pA∕Hz. We measure an upper limit on adjacent channel crosstalk of 0.004, which meets our design requirements. The demodulated noise spectra of multiplexed TESs are white at frequencies down to 200mHz.

DOI
10.1063/1.1884746

Related papers

Frequency-Domain SQUID Multiplexing of Transition-Edge Sensors

Trevor M. Lanting, Hsiao-Mei Cho, John L. Clarke +7 more

We describe our frequency-domain readout multiplexer for transition-edge sensor (TES) bolometers and present measurements of an eight-channel multiplexer. Each sensor is biased with a sinusoidal bias at a distinct frequency. As the sensor absorbs power, it amplitude-modulates its sinusoidal bias. Sensor currents are summed and measured with a single superconducting quantum interference device (SQUID) array. The SQUID array consists of 100 dc-SQUID's in series and is operated with shunt feedback electronics which have a slew rate of 1.210/sup 7/ /spl Phi//sub 0//s. A tuned filter consisting of an inductor and capacitor are placed in series with each sensor to both limit the bandwidth of the Nyquist noise from each sensor and to allow us to bias all multiplexed sensors with a common wire. We place an upper limit on crosstalk between adjacent channels of 0.004, well below our design requirements. Demodulated noise spectra from multiplexed sensors show the expected white noise levels at frequencies above 200 mHz.

IEEE Transactions on Applied Superconductivity•Jun 1, 2005•2 citations

Single SQUID multiplexer for arrays of voltage-biased superconducting bolometers

Jongsoo Yoon, John L. Clarke, Jan M. Gildemeister +5 more

We describe a frequency domain superconducting quantum interference device (SQUID) multiplexer which monitors a row of low-temperature sensors simultaneously with a single SQUID. Each sensor is ac biased with a unique frequency and all the sensor currents are added in a superconducting summing loop. A single SQUID measures the current in the summing loop, and the individual signals are lock-in detected after the room temperature SQUID electronics. The current in the summing loop is nulled by feedback to eliminate direct crosstalk. In order to avoid the accumulation of Johnson noise in the summing loop, a tuned bandpass filter is inserted in series with each sensor. For a 32-channel multiplexer for Voltage-biased Superconducting Bolometer (VSB) with a time constant {approx}1msec, we estimate that bias frequencies in the range from {approx}500kHz to {approx}600kHz are practical. The major limitation of our multiplexing scheme is in the slew rate of a readout SQUID. We discuss a ''carrier nulling'' technique which could be used to increase the number of sensors in a row or to multiplex faster bolometers by reducing the required slew rate for a readout SQUID.

Lawrence Berkeley National Laboratory•Aug 20, 2001•0 citations

Single SQUID multiplexer for arrays of Voltage-biased Superconducting Bolometers

Jongsoo Yoon, John L. Clarke, Jan M. Gildemeister +5 more

We describe a frequency domain superconducting quantum interference device (SQUID) multiplexer which monitors a row of low-temperature sensors simultaneously with a single SQUID. Each sensor is ac biased with a unique frequency and all the sensor currents are added in a superconducting summing loop. A single SQUID measures the current in the summing loop, and the individual signals are lock-in detected after the room temperature SQUID electronics. The current in the summing loop is nulled by feedback to eliminate direct crosstalk. In order to avoid the accumulation of Johnson noise in the summing loop, a tuned bandpass filter is inserted in series with each sensor. To multiplex 32 Voltage-biased Superconducting Bolometers (VSB) with 1 msec time constants a total bandwidth of 100 kHz is required. The minimum bias frequency is limited to ≳500 kHz by practical limitations in the size of photolithographed inductors and capacitors. The major limitation of our multiplexing scheme is in the slew rate of the readout SQUID. We discuss a “carrier nulling” technique which could be used to increase the number of sensors in a row or to multiplex faster bolometers by reducing the required slew rate for a readout SQUID.

AIP conference proceedings•Jan 1, 2002•3 citations

Single SQUID frequency-domain multiplexer for large bolometer arrays

Jongsoo Yoon, John L. Clarke, Jan M. Gildemeister +5 more

We describe the development of a frequency-domain superconducting quantum interference device (SQUID) multiplexer which monitors a row of low-temperature sensors simultaneously with a single SQUID. Each sensor is ac biased with a unique frequency and all the sensor currents are added in a superconducting summing loop. A single SQUID measures the current in the summing loop, and the individual signals are lock-in detected after the room temperature SQUID electronics. The current in the summing loop is nulled by feedback to eliminate direct crosstalk. We have built an eight-channel prototype and demonstrated channel separation and signal recovery.

•Aug 20, 2001•0 citations

A frequency-domain SQUID multiplexer for arrays of transition-edge superconducting sensors

Trevor M. Lanting, Hsiao-Mei Cho, John L. Clarke +5 more

We describe the development of a frequency-domain multiplexer (MUX) to read out arrays of superconducting transition-edge sensors (TES). Fabrication of large-format arrays of these sensors is becoming practical; however, reading out each sensor in the array is a major instrumental challenge. Frequency-domain multiplexing can greatly simplify the instrumentation of large arrays by reducing the number of SQUID's (superconducting quantum interference devices) and wires to the low temperature stages. Each sensor is AC biased at a different frequency, ranging from 380 kHz to 1 MHz. Each sensor signal amplitude-modulates its respective AC bias frequency. An LC filter associated with each sensor suppresses Johnson noise from the other sensors. The signals are combined at a current summing node and measured by a single SQUID. The individual signals from each sensor are then lock-in detected by room temperature electronics. Test chips with fully lithographed LC filters for up to 32 channels have been designed and fabricated. The capacitance and inductance values have been measured and are close to the design goals. We discuss the basic principles of frequency-domain multiplexing, the design and testing of the test chips, and the implementation of a practical system.

IEEE Transactions on Applied Superconductivity•Jun 1, 2003•20 citations

Frequency multiplexed superconducting quantum interference device readout of large bolometer arrays for cosmic microwave background measurements

M. Dobbs, Martin Lueker, K. A. Aird +44 more

A technological milestone for experiments employing transition edge sensor bolometers operating at sub-Kelvin temperature is the deployment of detector arrays with 100s-1000s of bolometers. One key technology for such arrays is readout multiplexing: the ability to read out many sensors simultaneously on the same set of wires. This paper describes a frequency-domain multiplexed readout system which has been developed for and deployed on the APEX-SZ and South Pole Telescope millimeter wavelength receivers. In this system, the detector array is divided into modules of seven detectors, and each bolometer within the module is biased with a unique ∼MHz sinusoidal carrier such that the individual bolometer signals are well separated in frequency space. The currents from all bolometers in a module are summed together and pre-amplified with superconducting quantum interference devices operating at 4 K. Room temperature electronics demodulate the carriers to recover the bolometer signals, which are digitized separately and stored to disk. This readout system contributes little noise relative to the detectors themselves, is remarkably insensitive to unwanted microphonic excitations, and provides a technology pathway to multiplexing larger numbers of sensors.

arXiv:1112.4215•Review of Scientific Instruments•Jul 1, 2012•138 citations
We demonstrate an eight-channel frequency-domain readout multiplexer for superconducting transition-edge sensors (TESs). Each sensor is biased with a sinusoidal voltage at a unique frequency. The sensor currents are summed and measured with a single superconducting quantum interference device (SQUID) array. The 100-element SQUID array is operated with shunt feedback electronics that have a slew rate of 1.2×107Φ0∕s at 1MHz. The multiplexer readout noise is 6.5pA∕Hz, which is well below the expected sensor noise of 15pA∕Hz. We measure an upper limit on adjacent channel crosstalk of 0.004, which meets our design requirements. The demodulated noise spectra of multiplexed TESs are white at frequencies down to 200mHz.
We describe our frequency-domain readout multiplexer for transition-edge sensor (TES) bolometers and present measurements of an eight-channel multiplexer. Each sensor is biased with a sinusoidal bias at a distinct frequency. As the sensor absorbs power, it amplitude-modulates its sinusoidal bias. Sensor currents are summed and measured with a single superconducting quantum interference device (SQUID) array. The SQUID array consists of 100 dc-SQUID's in series and is operated with shunt feedback electronics which have a slew rate of 1.210/sup 7/ /spl Phi//sub 0//s. A tuned filter consisting of an inductor and capacitor are placed in series with each sensor to both limit the bandwidth of the Nyquist noise from each sensor and to allow us to bias all multiplexed sensors with a common wire. We place an upper limit on crosstalk between adjacent channels of 0.004, well below our design requirements. Demodulated noise spectra from multiplexed sensors show the expected white noise levels at frequencies above 200 mHz.
We describe a frequency domain superconducting quantum interference device (SQUID) multiplexer which monitors a row of low-temperature sensors simultaneously with a single SQUID. Each sensor is ac biased with a unique frequency and all the sensor currents are added in a superconducting summing loop. A single SQUID measures the current in the summing loop, and the individual signals are lock-in detected after the room temperature SQUID electronics. The current in the summing loop is nulled by feedback to eliminate direct crosstalk. In order to avoid the accumulation of Johnson noise in the summing loop, a tuned bandpass filter is inserted in series with each sensor. For a 32-channel multiplexer for Voltage-biased Superconducting Bolometer (VSB) with a time constant {approx}1msec, we estimate that bias frequencies in the range from {approx}500kHz to {approx}600kHz are practical. The major limitation of our multiplexing scheme is in the slew rate of a readout SQUID. We discuss a ''carrier nulling'' technique which could be used to increase the number of sensors in a row or to multiplex faster bolometers by reducing the required slew rate for a readout SQUID.
We describe a frequency domain superconducting quantum interference device (SQUID) multiplexer which monitors a row of low-temperature sensors simultaneously with a single SQUID. Each sensor is ac biased with a unique frequency and all the sensor currents are added in a superconducting summing loop. A single SQUID measures the current in the summing loop, and the individual signals are lock-in detected after the room temperature SQUID electronics. The current in the summing loop is nulled by feedback to eliminate direct crosstalk. In order to avoid the accumulation of Johnson noise in the summing loop, a tuned bandpass filter is inserted in series with each sensor. To multiplex 32 Voltage-biased Superconducting Bolometers (VSB) with 1 msec time constants a total bandwidth of 100 kHz is required. The minimum bias frequency is limited to ≳500 kHz by practical limitations in the size of photolithographed inductors and capacitors. The major limitation of our multiplexing scheme is in the slew rate of the readout SQUID. We discuss a “carrier nulling” technique which could be used to increase the number of sensors in a row or to multiplex faster bolometers by reducing the required slew rate for a readout SQUID.
We describe the development of a frequency-domain superconducting quantum interference device (SQUID) multiplexer which monitors a row of low-temperature sensors simultaneously with a single SQUID. Each sensor is ac biased with a unique frequency and all the sensor currents are added in a superconducting summing loop. A single SQUID measures the current in the summing loop, and the individual signals are lock-in detected after the room temperature SQUID electronics. The current in the summing loop is nulled by feedback to eliminate direct crosstalk. We have built an eight-channel prototype and demonstrated channel separation and signal recovery.
We describe the development of a frequency-domain multiplexer (MUX) to read out arrays of superconducting transition-edge sensors (TES). Fabrication of large-format arrays of these sensors is becoming practical; however, reading out each sensor in the array is a major instrumental challenge. Frequency-domain multiplexing can greatly simplify the instrumentation of large arrays by reducing the number of SQUID's (superconducting quantum interference devices) and wires to the low temperature stages. Each sensor is AC biased at a different frequency, ranging from 380 kHz to 1 MHz. Each sensor signal amplitude-modulates its respective AC bias frequency. An LC filter associated with each sensor suppresses Johnson noise from the other sensors. The signals are combined at a current summing node and measured by a single SQUID. The individual signals from each sensor are then lock-in detected by room temperature electronics. Test chips with fully lithographed LC filters for up to 32 channels have been designed and fabricated. The capacitance and inductance values have been measured and are close to the design goals. We discuss the basic principles of frequency-domain multiplexing, the design and testing of the test chips, and the implementation of a practical system.
A technological milestone for experiments employing transition edge sensor bolometers operating at sub-Kelvin temperature is the deployment of detector arrays with 100s-1000s of bolometers. One key technology for such arrays is readout multiplexing: the ability to read out many sensors simultaneously on the same set of wires. This paper describes a frequency-domain multiplexed readout system which has been developed for and deployed on the APEX-SZ and South Pole Telescope millimeter wavelength receivers. In this system, the detector array is divided into modules of seven detectors, and each bolometer within the module is biased with a unique ∼MHz sinusoidal carrier such that the individual bolometer signals are well separated in frequency space. The currents from all bolometers in a module are summed together and pre-amplified with superconducting quantum interference devices operating at 4 K. Room temperature electronics demodulate the carriers to recover the bolometer signals, which are digitized separately and stored to disk. This readout system contributes little noise relative to the detectors themselves, is remarkably insensitive to unwanted microphonic excitations, and provides a technology pathway to multiplexing larger numbers of sensors.