TY - JOUR
AU - Juan Muniz
AU - Dylan Young
AU - Julia Cline
AU - James Thompson
AB - We demonstrate the direct quantum nondemolition detection of a millihertz linewidth optical atomic transition. We observe the modification of the phase and amplitude of a probe field interacting with strontium atoms, which provides a direct spectroscopic signal to which a laser could be frequency stabilized. To investigate this measurement capability, we demonstrate an approach to determining the intrinsic natural lifetime of exceptionally long-lived optical excited states. Such transitions are key to the performance of state-of-the-art atomic clocks, have potential applications in searches for fundamental physics and gravitational wave detectors, as well as quantum many-body phenomena. Here, we determine the ratio of the challenging to measure and poorly known ultranarrow linewidth transition( 3 P 0  to  1 S 0  in  87 Sr )to that of another narrow well-known transition ( 3 P 1  to  1 S 0 )  by coupling the two transitions to a single optical cavity and performing interleaved nondestructive measurements of the interaction strengths of the atoms with cavity modes near each transition frequency. We use this approach to determine the natural linewidth of the clock transition γ 0 / ( 2 π ) = 1.35 ( 3 )  mHz or  τ = 118 ( 3 )  s. The 30- μ Hz resolution implies that we could detect states with lifetimes just below 2 h, and with straightforward future improvements, we could detect states with lifetimes up to 15 h, using measurement trials that last only a few hundred milliseconds, eliminating the need for long storage times in optical potentials. This work opens the path to nondestructive direct spectroscopy of ultranarrow transition for continuous frequency measurements and laser stabilization.
BT - Physical Review Research
DA - 2021-05
DO - 10.1103/PhysRevResearch.3.023152
N2 - We demonstrate the direct quantum nondemolition detection of a millihertz linewidth optical atomic transition. We observe the modification of the phase and amplitude of a probe field interacting with strontium atoms, which provides a direct spectroscopic signal to which a laser could be frequency stabilized. To investigate this measurement capability, we demonstrate an approach to determining the intrinsic natural lifetime of exceptionally long-lived optical excited states. Such transitions are key to the performance of state-of-the-art atomic clocks, have potential applications in searches for fundamental physics and gravitational wave detectors, as well as quantum many-body phenomena. Here, we determine the ratio of the challenging to measure and poorly known ultranarrow linewidth transition( 3 P 0  to  1 S 0  in  87 Sr )to that of another narrow well-known transition ( 3 P 1  to  1 S 0 )  by coupling the two transitions to a single optical cavity and performing interleaved nondestructive measurements of the interaction strengths of the atoms with cavity modes near each transition frequency. We use this approach to determine the natural linewidth of the clock transition γ 0 / ( 2 π ) = 1.35 ( 3 )  mHz or  τ = 118 ( 3 )  s. The 30- μ Hz resolution implies that we could detect states with lifetimes just below 2 h, and with straightforward future improvements, we could detect states with lifetimes up to 15 h, using measurement trials that last only a few hundred milliseconds, eliminating the need for long storage times in optical potentials. This work opens the path to nondestructive direct spectroscopy of ultranarrow transition for continuous frequency measurements and laser stabilization.
PY - 2021
EP - 023152
T2 - Physical Review Research
TI - Cavity-QED measurements of the 87Sr millihertz optical clock transition and determination of its natural linewidth
UR - https://journals.aps.org/prresearch/abstract/10.1103/PhysRevResearch.3.023152
VL - 3
ER -