Ion-trap-integrated superconducting photon detectors for qubit readout

by Daniel Slichter

Thursday 27 May 2021, 16:00 → 17:30 Europe/Zurich

CERN

Trapped atomic ions are an important technology for quantum computing, quantum sensing, and atomic frequency standards.  These applications all rely on high-fidelity readout of the quantum state of a trapped ion qubit, which is accomplished by driving a state-selective optical cycling transition of the trapped ion and counting the resulting fluorescence photons; the presence or absence of fluorescence indicates the ion qubit state. These photons are traditionally collected with high-numerical-aperture bulk optics and detected with a camera or photomultiplier tube.  To aid in scaling of quantum systems, or in cases where optical access is at a premium or even unavailable, it may be desirable to detect these fluorescence photons with photon detectors integrated directly into the ion trap structure.  The paradigm of trap-integrated detectors leverages existing efforts on making planar surface-electrode ion traps using microfabrication techniques.  

Our work in this area is focused on integrating superconducting nanowire single photon detectors (SNSPDs) into surface-electrode rf ion traps.  SNSPDs are a versatile class of photon-counting detectors exhibiting near-unity detection efficiencies, fast response times, low timing jitter, and very low dark counts over a broad range of wavelengths.  By integrating SNSPDs directly into microfabricated surface-electrode ion traps, we can realize a scalable architecture for spatially-resolved, high-quantum-efficiency detection of fluorescence photons without the need for collection optics.  

In this talk, I will describe recent results on high-fidelity quantum state detection of a single 9Be+ ion hyperfine qubit in a cryogenic surface-electrode trap using a trap-integrated SNSPD.  The SNSPD counts ion fluorescence photons at 313 nm, providing qubit state readout with an average fidelity of 0.9991(1) and a mean readout duration of 46µs.  The fidelity is limited by the polarization impurity of the readout laser beam and by off-resonant optical pumping.  Because there are no intervening optical elements between the ion and the detector, we can use the ion fluorescence as a self-calibrated photon source to determine the detector quantum efficiency and its dependence on photon incidence angle and polarization.  We report the impact of the detector on motional heating of the ion, and discuss the sensitivity of the detector to fluorescence from an ion located in another region of the trap. This work is supported by IARPA and the NIST Quantum Information Program.  

To participate in this seminar, check this link

https://us04web.zoom.us/j/932734874

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In case of questions contact Stefan Ulmer (stefan.ulmer@cern.ch)

Trapped atomic ions are an important technology for quantum computing, quantum sensing, and atomic frequency standards.  These applications all rely on high-fidelity readout of the quantum state of a trapped ion qubit, which is accomplished by driving a state-selective optical cycling transition of the trapped ion and counting the resulting fluorescence photons; the presence or absence of fluorescence indicates the ion qubit state. These photons are traditionally collected with high-numerical-aperture bulk optics and detected with a camera or photomultiplier tube.  To aid in scaling of quantum systems, or in cases where optical access is at a premium or even unavailable, it may be desirable to detect these fluorescence photons with photon detectors integrated directly into the ion trap structure.  The paradigm of trap-integrated detectors leverages existing efforts on making planar surface-electrode ion traps using microfabrication techniques.  

Our work in this area is focused on integrating superconducting nanowire single photon detectors (SNSPDs) into surface-electrode rf ion traps.  SNSPDs are a versatile class of photon-counting detectors exhibiting near-unity detection efficiencies, fast response times, low timing jitter, and very low dark counts over a broad range of wavelengths.  By integrating SNSPDs directly into microfabricated surface-electrode ion traps, we can realize a scalable architecture for spatially-resolved, high-quantum-efficiency detection of fluorescence photons without the need for collection optics.  

In this talk, I will describe recent results on high-fidelity quantum state detection of a single 9Be+ ion hyperfine qubit in a cryogenic surface-electrode trap using a trap-integrated SNSPD.  The SNSPD counts ion fluorescence photons at 313 nm, providing qubit state readout with an average fidelity of 0.9991(1) and a mean readout duration of 46µs.  The fidelity is limited by the polarization impurity of the readout laser beam and by off-resonant optical pumping.  Because there are no intervening optical elements between the ion and the detector, we can use the ion fluorescence as a self-calibrated photon source to determine the detector quantum efficiency and its dependence on photon incidence angle and polarization.  We report the impact of the detector on motional heating of the ion, and discuss the sensitivity of the detector to fluorescence from an ion located in another region of the trap. This work is supported by IARPA and the NIST Quantum Information Program.  

To participate in this seminar, check this link

https://us04web.zoom.us/j/932734874

---

In case of questions contact Stefan Ulmer (stefan.ulmer@cern.ch)

Trapped atomic ions are an important technology for quantum computing, quantum sensing, and atomic frequency standards.  These applications all rely on high-fidelity readout of the quantum state of a trapped ion qubit, which is accomplished by driving a state-selective optical cycling transition of the trapped ion and counting the resulting fluorescence photons; the presence or absence of fluorescence indicates the ion qubit state. These photons are traditionally collected with high-numerical-aperture bulk optics and detected with a camera or photomultiplier tube.  To aid in scaling of quantum systems, or in cases where optical access is at a premium or even unavailable, it may be desirable to detect these fluorescence photons with photon detectors integrated directly into the ion trap structure.  The paradigm of trap-integrated detectors leverages existing efforts on making planar surface-electrode ion traps using microfabrication techniques.  

Our work in this area is focused on integrating superconducting nanowire single photon detectors (SNSPDs) into surface-electrode rf ion traps.  SNSPDs are a versatile class of photon-counting detectors exhibiting near-unity detection efficiencies, fast response times, low timing jitter, and very low dark counts over a broad range of wavelengths.  By integrating SNSPDs directly into microfabricated surface-electrode ion traps, we can realize a scalable architecture for spatially-resolved, high-quantum-efficiency detection of fluorescence photons without the need for collection optics.  

In this talk, I will describe recent results on high-fidelity quantum state detection of a single 9Be+ ion hyperfine qubit in a cryogenic surface-electrode trap using a trap-integrated SNSPD.  The SNSPD counts ion fluorescence photons at 313 nm, providing qubit state readout with an average fidelity of 0.9991(1) and a mean readout duration of 46µs.  The fidelity is limited by the polarization impurity of the readout laser beam and by off-resonant optical pumping.  Because there are no intervening optical elements between the ion and the detector, we can use the ion fluorescence as a self-calibrated photon source to determine the detector quantum efficiency and its dependence on photon incidence angle and polarization.  We report the impact of the detector on motional heating of the ion, and discuss the sensitivity of the detector to fluorescence from an ion located in another region of the trap. This work is supported by IARPA and the NIST Quantum Information Program.  

To participate in this seminar, check this link

https://us04web.zoom.us/j/932734874

---

Trapped atomic ions are an important technology for quantum computing, quantum sensing, and atomic frequency standards.  These applications all rely on high-fidelity readout of the quantum state of a trapped ion qubit, which is accomplished by driving a state-selective optical cycling transition of the trapped ion and counting the resulting fluorescence photons; the presence or absence of fluorescence indicates the ion qubit state. These photons are traditionally collected with high-numerical-aperture bulk optics and detected with a camera or photomultiplier tube.  To aid in scaling of quantum systems, or in cases where optical access is at a premium or even unavailable, it may be desirable to detect these fluorescence photons with photon detectors integrated directly into the ion trap structure.  The paradigm of trap-integrated detectors leverages existing efforts on making planar surface-electrode ion traps using microfabrication techniques.  

Our work in this area is focused on integrating superconducting nanowire single photon detectors (SNSPDs) into surface-electrode rf ion traps.  SNSPDs are a versatile class of photon-counting detectors exhibiting near-unity detection efficiencies, fast response times, low timing jitter, and very low dark counts over a broad range of wavelengths.  By integrating SNSPDs directly into microfabricated surface-electrode ion traps, we can realize a scalable architecture for spatially-resolved, high-quantum-efficiency detection of fluorescence photons without the need for collection optics.  

In this talk, I will describe recent results on high-fidelity quantum state detection of a single 9Be+ ion hyperfine qubit in a cryogenic surface-electrode trap using a trap-integrated SNSPD.  The SNSPD counts ion fluorescence photons at 313 nm, providing qubit state readout with an average fidelity of 0.9991(1) and a mean readout duration of 46µs.  The fidelity is limited by the polarization impurity of the readout laser beam and by off-resonant optical pumping.  Because there are no intervening optical elements between the ion and the detector, we can use the ion fluorescence as a self-calibrated photon source to determine the detector quantum efficiency and its dependence on photon incidence angle and polarization.  We report the impact of the detector on motional heating of the ion, and discuss the sensitivity of the detector to fluorescence from an ion located in another region of the trap. This work is supported by IARPA and the NIST Quantum Information Program.  

To participate in this seminar, check this link

https://us04web.zoom.us/j/932734874

---

Trapped atomic ions are an important technology for quantum computing, quantum sensing, and atomic frequency standards.  These applications all rely on high-fidelity readout of the quantum state of a trapped ion qubit, which is accomplished by driving a state-selective optical cycling transition of the trapped ion and counting the resulting fluorescence photons; the presence or absence of fluorescence indicates the ion qubit state. These photons are traditionally collected with high-numerical-aperture bulk optics and detected with a camera or photomultiplier tube.  To aid in scaling of quantum systems, or in cases where optical access is at a premium or even unavailable, it may be desirable to detect these fluorescence photons with photon detectors integrated directly into the ion trap structure.  The paradigm of trap-integrated detectors leverages existing efforts on making planar surface-electrode ion traps using microfabrication techniques.  

Our work in this area is focused on integrating superconducting nanowire single photon detectors (SNSPDs) into surface-electrode rf ion traps.  SNSPDs are a versatile class of photon-counting detectors exhibiting near-unity detection efficiencies, fast response times, low timing jitter, and very low dark counts over a broad range of wavelengths.  By integrating SNSPDs directly into microfabricated surface-electrode ion traps, we can realize a scalable architecture for spatially-resolved, high-quantum-efficiency detection of fluorescence photons without the need for collection optics.  

In this talk, I will describe recent results on high-fidelity quantum state detection of a single 9Be+ ion hyperfine qubit in a cryogenic surface-electrode trap using a trap-integrated SNSPD.  The SNSPD counts ion fluorescence photons at 313 nm, providing qubit state readout with an average fidelity of 0.9991(1) and a mean readout duration of 46µs.  The fidelity is limited by the polarization impurity of the readout laser beam and by off-resonant optical pumping.  Because there are no intervening optical elements between the ion and the detector, we can use the ion fluorescence as a self-calibrated photon source to determine the detector quantum efficiency and its dependence on photon incidence angle and polarization.  We report the impact of the detector on motional heating of the ion, and discuss the sensitivity of the detector to fluorescence from an ion located in another region of the trap. This work is supported by IARPA and the NIST Quantum Information Program.  

To participate in this seminar, check this link

https://us04web.zoom.us/j/932734874

---

Trapped atomic ions are an important technology for quantum computing, quantum sensing, and atomic frequency standards.  These applications all rely on high-fidelity readout of the quantum state of a trapped ion qubit, which is accomplished by driving a state-selective optical cycling transition of the trapped ion and counting the resulting fluorescence photons; the presence or absence of fluorescence indicates the ion qubit state. These photons are traditionally collected with high-numerical-aperture bulk optics and detected with a camera or photomultiplier tube.  To aid in scaling of quantum systems, or in cases where optical access is at a premium or even unavailable, it may be desirable to detect these fluorescence photons with photon detectors integrated directly into the ion trap structure.  The paradigm of trap-integrated detectors leverages existing efforts on making planar surface-electrode ion traps using microfabrication techniques.  

Our work in this area is focused on integrating superconducting nanowire single photon detectors (SNSPDs) into surface-electrode rf ion traps.  SNSPDs are a versatile class of photon-counting detectors exhibiting near-unity detection efficiencies, fast response times, low timing jitter, and very low dark counts over a broad range of wavelengths.  By integrating SNSPDs directly into microfabricated surface-electrode ion traps, we can realize a scalable architecture for spatially-resolved, high-quantum-efficiency detection of fluorescence photons without the need for collection optics.  

In this talk, I will describe recent results on high-fidelity quantum state detection of a single 9Be+ ion hyperfine qubit in a cryogenic surface-electrode trap using a trap-integrated SNSPD.  The SNSPD counts ion fluorescence photons at 313 nm, providing qubit state readout with an average fidelity of 0.9991(1) and a mean readout duration of 46µs.  The fidelity is limited by the polarization impurity of the readout laser beam and by off-resonant optical pumping.  Because there are no intervening optical elements between the ion and the detector, we can use the ion fluorescence as a self-calibrated photon source to determine the detector quantum efficiency and its dependence on photon incidence angle and polarization.  We report the impact of the detector on motional heating of the ion, and discuss the sensitivity of the detector to fluorescence from an ion located in another region of the trap. This work is supported by IARPA and the NIST Quantum Information Program.  

To participate in this seminar, check this link

https://us04web.zoom.us/j/932734874

---