A5101826138- Cold Atom Physics and Bose-Einstein Condensates
- Advanced Frequency and Time Standards
- Atomic and Subatomic Physics Research
- Quantum optics and atomic interactions
- Atomic and Molecular Physics
- Physics of Superconductivity and Magnetism
- Spectroscopy and Laser Applications
- Quantum, superfluid, helium dynamics
- Scientific Measurement and Uncertainty Evaluation
- Laser Design and Applications
- Superconducting Materials and Applications
- Magnetic properties of thin films
- Geophysics and Sensor Technology
- Advanced Fiber Laser Technologies
- Photonic and Optical Devices
University of Birmingham
2019-2023
BT Group (United Kingdom)
2023
Indian Institute of Science Bangalore
2009-2017
Defence Metallurgical Research Laboratory
1997
Indira Gandhi Centre for Atomic Research
1996
We apply our technique of using a Rb-stabilized ring-cavity resonator to measure the frequencies various spectral components in 555.8-nm ${^{1}S}_{0}\ensuremath{\rightarrow}{^{3}P}_{1}$ line Yb. determine isotope shifts with 60 kHz precision, which is an order-of-magnitude improvement over best previous measurement on this line. There are two overlapping transitions, $^{171}\text{Y}\text{b}(1/2\ensuremath{\rightarrow}3/2)$ and $^{173}\text{Y}\text{b}(5/2\ensuremath{\rightarrow}3/2)$, we...
Abstract Recently, several reports with a strong focus on compact, nonstationary optical atomic clocks have been published, including accounts of in-field deployment these devices for demonstrations chronometric levelling in different types environments. We review recent progress this research area, comprising compact and transportable neutral atom single-ion clocks. The identified strive low volume, weight power consumption while exceeding standard microwave fractional frequency instability...
We measure hyperfine structure in the metastable ${{}^{3}P}_{2}$ state of ${}^{173}$Yb and extract nuclear magnetic octupole moment. populate using dipole-allowed transitions through ${{}^{3}P}_{1}$ ${{}^{3}S}_{1}$ states. frequencies ${{}^{3}P}_{2}\ensuremath{\rightarrow}{{}^{3}S}_{1}$ line at 770 nm a Rb-stabilized ring cavity resonator with precision 200 kHz. Second-order corrections due to perturbations from nearby ${{}^{1}P}_{1}$ states are below 30 obtain coefficients as...
We demonstrate launching of laser-cooled Yb atoms in a cold atomic fountain. Atoms collimated thermal beam are first cooled and captured magneto-optical trap (MOT) operating on the strongly allowed ${{}^{1}S}_{0}\ensuremath{\rightarrow}{{}^{1}P}_{1}$ transition at 399 nm (blue line). They then transferred to MOT weakly ${{}^{1}S}_{0}\ensuremath{\rightarrow}{{}^{3}P}_{1}$ 556 (green Cold from green launched against gravity velocity around 2.5 m/s using pair beams. more than ${10}^{7}$ blue...
We report a precise measurement of the hyperfine interval in ${2P}_{1/2}$ state $^{7}$Li. The transition from ground ($D_1$ line) is accessed using diode laser and technique saturated-absorption spectroscopy hot Li vapor. measured by locking an acousto-optic modulator to frequency difference between two peaks. 92.040(6)~MHz consistent with earlier reported us atomic-beam spectrometer [Das Natarajan, J.\ Phys.\ B {\bf 41}, 035001 (2008)]. yields magnetic dipole constant $P_{1/2}$ as...
Abstract An atomics package is the heart of any atom based quantum sensing device. Here we report on realisation a field deployable for alkaline earth atoms, e.g. Sr or Yb. In terms size (∼121 L), weight (<75 kg) and power (∼320 W), it smallest to date which designed load atoms into an optical lattice. It consists ultra-high vacuum assembly (<4 lasers, magnetic coils & optics required cooling trapping as well module imaging detection. The can routinely produce ultra cold dense...
We have developed a technique to measure the absolute frequencies of optical transitions by using an evacuated Rb-stabilized ring-cavity resonator as transfer cavity. study possible wavelength-dependent errors due dispersion at cavity mirrors measuring frequency same transition in $D_2$ line Cs three lengths. find no discernable change values within our error 30 kHz. Our are consistent with measurements frequency-comb and similar accuracy.
We demonstrate launching of laser-cooled Yb atoms in a continuous atomic beam. The cold beam has significant advantages over the more-common pulsed fountain, which was also demonstrated by us recently. is formed following steps---(i) Atoms from thermal are first Zeeman slowed to small final velocity, (ii) captured two-dimensional magneto-optic trap (2D-MOT), and (iii) launched {\em continuously} vertical direction using two sets moving-molasses beams, inclined at $\pm 15^\circ$ vertical....
We study coherent population oscillations in an odd isotope of the two-electron atom Yb. The experiments are done using magnetic sublevels hyperfine transition 173Yb intercombination line. both with and without applied field. In absence field, complicated sublevel structure along saturated fluorescence effect causes linewidth to be larger than 190 kHz natural transition. presence a field (of magnitude 330 mG), well-defined quantization axis is present which results formation two M-type...
The development of a portable strontium lattice clock is discussed. Solutions to many the engineering challenges required build next generation and ultraprecise clocks will be presented. In particular, a) realisation compact laser module which produces multiple stable frequencies for experiment b) progress made in atomics module.
We observe coherent population trapping (CPT) in a two-electron atom---$^{174}$Yb---using the $\rm {^1S_0,F=0} \rightarrow {^3P_1,F'=1}$ transition. CPT is not possible for such transition according to one-electron theory because magnetic sublevels form V-type system, but atom like Yb, interaction of electrons transforms level structure into $ \Lambda $-type which allows formation dark state and hence observation CPT. Since two levels involved are degenerate, we use field lift degeneracy....
We present our work on a compact and flexible Optical Lattice Clock Testbed System. This system helps realizing transportable strontium-based optical atomic clock demonstrator built from industry-developed subsystems – deliverable of the iqClock project. The will be integrated at University Birmingham. In order to facilitate integration demonstrator, we use testbed assess performance industry-built components subsystems. is completed in its first phase, capable ultra-cold atoms. subsequent...
In this report, we present our work towards the development of strontium based optical lattice clock testbed system [1]. This facilitates accomplishment a compact and transportable strontium-based atomic (one two goals iqClock project [2]) built from components developed by industrial partners. The allows us to benchmark access performance subsystems. With task completed, have been extending constitute fully-fledged clock. main results includes: - 1) Two stage laser cooling <sup...
We have shown earlier that hyperfine spectroscopy in a vapor cell using co-propagating pump-probe beams has many advantages over the usual technique of saturated-absorption counter-propagating beams. The main are absence crossover resonances, appearance signal on flat (Doppler-free) background, and higher signal-to-noise ratio primary peaks. Interaction with non-zero-velocity atoms causes additional peaks, but only one them appears within spectrum. first illustrate this for high-resolution...