Proposal for a rotation-sensing interferometer with spin-orbit-coupled atoms

We propose a theoretical scheme to realize a rotation-sensing interferometer with spin-orbit coupled atoms. The sensitivity of this interferometer is dependent on the atomic mass $m^{-\alpha }$ with a factor $\alpha ⩾1$. Thus, the sensitivity can be improved by about one order of magnitude when we choose Li instead of Rb. Furthermore, compared to the standard Raman interferometer, the response to high-frequency, time-dependent rotation can be improved through the continuous coupling between spin and orbital freedoms of the atoms.

Figure 1

(a) Three-level $\Lambda$ atomic system coupled with two laser beams characterized by the Rabi frequencies ${\Omega }_1$ and ${\Omega }_2$ with a large single-photon detuning $\Delta$. (b) Schematic representation of laser-atom interaction. The Rabi frequencies ${\Omega }_1$, ${\Omega }_2$ are space-dependent and will exist along the whole process, while $P\left(t\right)$ are the $\pi /2-\pi -\pi /2$ sequences in the dressed states.

Figure 2

(a) The distribution of synthetic magnetic field along $x$ axis with different parameter $q$. (b, c) Spin-dependent trajectories of a single Rb atom in (b) and atom Li in (c) during the procession in the rotating frame $\omega$. The division of superposition state induced by the space-dependent Rabi frequencies is illustrated by the blue solid lines. We recombine the atom by a $\pi$ pulse and then the atom is traveling along the red dashed lines and interfere at point $M$. The atoms collected by the collectors $C_1$, $C_2$ will be used to examine the interference induced by rotation $\omega$. The other parameters $\Delta x_0=2.5\mu$m, ${\sigma }_0=10\mu$m and $k={10}^7$  ${\mathrm{m}}^{-1}$.

Figure 3

The relationship between the division time $t_d$ and the recombination time $t_c$.

Figure 4

(a) The enclosing area $S$ versus parameter $q$ with the division time $t_d=0.4\mathrm{ms}$. (b) Area $S$ verses the ratio $m/m_0$ with different max operating time.

Figure 5

(a) Enclosing area in Raman-type interferometers (blue solid line) and in the $SO$ coupling with $q=1.11$ (red dotted line), $q=1.43$ (black dashed line), and $t_d=0.2\mathrm{ms}$. As can be seen that the interferometry using gauge field will dominate at lighter mass elements such as lithium and sodium. (b) The response factors toward sinusoidal time-varying signal for Raman and $SO$-type interferometers.