I will present our development of global-phase spectroscopy, a Rabi-like metrological protocol inspired by geometric control techniques originally introduced for holonomic quantum gates and based on detuning-dependent Aharonov–Anandan phase. Applied to an optical clock transition, we deployed this method to realize quantum-amplified, time-reversal spectroscopy, yielding 2.4(7) dB metrological gain and 4.0(8) dB laser-noise suppression beyond the standard quantum limit. I will focus on the key metrological advantages of global-phase spectroscopy: i) an intrinsically favorable scaling of sensitivity to local-oscillator high-frequency noise (compared to for Rabi and for Ramsey), and, unlike standard Rabi spectroscopy, ii) featuring quantum enhancement when operated with entangled collective states, such as spin-squeezed inputs. I will close by connecting these results to the broader QIS-NP landscape, highlighting opportunities for applying this protocol to (other) nuclear-spin qubits, nuclear clocks, and other emerging quantum-enhanced sensing and quantum-information platforms.I will present our development of global-phase spectroscopy, a Rabi-like metrological protocol inspired by geometric control techniques originally introduced for holonomic quantum gates and based on detuning-dependent Aharonov–Anandan phase. Applied to an optical clock transition, we deployed this method to realize quantum-amplified, time-reversal spectroscopy, yielding 2.4(7) dB metrological gain and 4.0(8) dB laser-noise suppression beyond the standard quantum limit. I will focus on the key metrological advantages of global-phase spectroscopy: i) an intrinsically favorable scaling of sensitivity to local-oscillator high-frequency noise (compared to for Rabi and for Ramsey), and, unlike standard Rabi spectroscopy, ii) featuring quantum enhancement when operated with entangled collective states, such as spin-squeezed inputs. I will close by connecting these results to the broader QIS-NP landscape, highlighting opportunities for applying this protocol to (other) nuclear-spin qubits, nuclear clocks, and other emerging quantum-enhanced sensing and quantum-information platforms.

Optical and Quantum Sensing and Precision Metrology IIMar 5, 20260 citations

Optical-Transition Atomic Clock Beyond the Standard Quantum Limit

Vladan Vuletić

Feb 12, 20210 citations

Hyper-Ramsey spectroscopy of optical clock transitions

Valeriy I. Yudin, А. В. Тайченачев, Chris W. Oates +6 more

We present nonstandard optical Ramsey schemes that use pulses individually tailored in duration, phase, and frequency to cancel spurious frequency shifts related to the excitation itself. In particular, the field shifts and their uncertainties can be radically suppressed (by two to four orders of magnitude) in comparison with the usual Ramsey method (using two equal pulses) as well as with single-pulse Rabi spectroscopy. Atom interferometers and optical clocks based on two-photon transitions, heavily forbidden transitions, or magnetically induced spectroscopy could significantly benefit from this method. In the latter case, these frequency shifts can be suppressed considerably below a fractional level of $10$ ${}^{\ensuremath{-}17}$. Moreover, our approach opens the door for high-precision optical clocks based on direct frequency comb spectroscopy.We present nonstandard optical Ramsey schemes that use pulses individually tailored in duration, phase, and frequency to cancel spurious frequency shifts related to the excitation itself. In particular, the field shifts and their uncertainties can be radically suppressed (by two to four orders of magnitude) in comparison with the usual Ramsey method (using two equal pulses) as well as with single-pulse Rabi spectroscopy. Atom interferometers and optical clocks based on two-photon transitions, heavily forbidden transitions, or magnetically induced spectroscopy could significantly benefit from this method. In the latter case, these frequency shifts can be suppressed considerably below a fractional level of $10$${}^{\ensuremath{-}17}$. Moreover, our approach opens the door for high-precision optical clocks based on direct frequency comb spectroscopy.

arXiv:0910.5948Physical Review AJul 22, 2010139 citations

Autobalanced Ramsey Spectroscopy

Christian Sanner, Nils Huntemann, R. Lange +2 more

We devise a perturbation-immune version of Ramsey's method of separated oscillatory fields. Spectroscopy of an atomic clock transition without compromising the clock's accuracy is accomplished by actively balancing the spectroscopic responses from phase-congruent Ramsey probe cycles of unequal durations. Our simple and universal approach eliminates a wide variety of interrogation-induced line shifts often encountered in high precision spectroscopy, among them, in particular, light shifts, phase chirps, and transient Zeeman shifts. We experimentally demonstrate autobalanced Ramsey spectroscopy on the light shift prone ^{171}Yb^{+} electric octupole optical clock transition and show that interrogation defects are not turned into clock errors. This opens up frequency accuracy perspectives below the 10^{-18} level for the Yb^{+} system and for other types of optical clocks.We devise a perturbation-immune version of Ramsey's method of separated oscillatory fields. Spectroscopy of an atomic clock transition without compromising the clock's accuracy is accomplished by actively balancing the spectroscopic responses from phase-congruent Ramsey probe cycles of unequal durations. Our simple and universal approach eliminates a wide variety of interrogation-induced line shifts often encountered in high precision spectroscopy, among them, in particular, light shifts, phase chirps, and transient Zeeman shifts. We experimentally demonstrate autobalanced Ramsey spectroscopy on the light shift prone ^{171}Yb^{+} electric octupole optical clock transition and show that interrogation defects are not turned into clock errors. This opens up frequency accuracy perspectives below the 10^{-18} level for the Yb^{+} system and for other types of optical clocks.

arXiv:1707.02630Physical Review LettersJan 30, 201876 citations

10

${}^{\ensuremath{-}17}$. Moreover, our approach opens the door for high-precision optical clocks based on direct frequency comb spectroscopy.