We present a novel matter-wave gyroscope employing a superposition of two counter-rotating vortices in Bose-Einstein condensates that can be generated using orbital angular momentum of light. We also discuss the sensitivity of such a device.
Matter–wave interferometers are, in principle, orders of magnitude more sensitive than their optical counterparts. Nevertheless, creation of matter–wave currents to achieve such a sensitivity is a continuing challenge. Here, we propose the use of Optical-Angular-Momentum (OAM) induced vortex superpositions in Bose–Einstein condensates (BECs) as an alternative to other atom interferometers for gyroscopy. The coherent superposition of two counter-rotating vortex states of a trapped condensate leads to an interference pattern that rotates by an angle proportional to the angular velocity of the rotating trap – in accordance with the Sagnac effect. We show that the rotation rate can be easily read out, and that the device is highly stable. The signal-to-noise ratio and sensitivity of the scheme are also estimated.
With high precision and sensitivity, quantum gyroscope has become a research hotspot of inertial technology in recent years. Because the Bose-Einstein Condensate (BEC) in atomic gas has more condensate atoms, atomic gas is pure and thin, and there is no friction in atoms, the matter–wave gyroscopy with counter-rotating vortex superpositions has great potential of higher sensitivity, higher precision, and miniaturization. The basic mechanism and sensitivity of the matter– wave gyroscopy with counter-rotating vortex superpositions were analyzed, and the interaction between superposition of vortex beams and BEC atomic gases were studied, it is Stimulated Raman Adiabatic Passage (STIRAP). In the study, the outstanding issue that the gyroscopy is difficult to obtain stable vortices with high order orbital angular momentum was clarified by theoretical derivation on the base of Gross-Pitaevskii equation which is the basic equation in BEC. For solving the above problems, the scheme which is easy to achieve based on Sombrero potential trap was proposed.
We propose a scheme for the generation of arbitrary coherent superpositions of vortex states in Bose-Einstein condensates (BEC) using the orbital-angular-momentum states of light. We devise a scheme to generate coherent superpositions of two such counterrotating states of light using well-known experimental techniques. We show that a specially designed Raman scheme allows for transfer of the optical vortex-superposition state onto an initially nonrotating BEC. This creates an arbitrary and coherent superposition of a vortex and antivortex pair in the BEC. The ideas presented here could be extended to generate entangled vortex states, design memories for the orbital-angular-momentum states of light, and perform other quantum information tasks. Applications to inertial sensing are also discussed.
Vortex nucleation is the key technology to realize quantum gyroscope in Bose-Einstein Condensates (BEC). Through mass investigation and research, the recent research status of vortex nucleation in Bose-Einstein Condensates is presented, the theory and experimentation about imprinting phase, rotating the potential trap and transferring the orbital angular momentum of a photon to generate BEC vortex are analyzed and compared in detail, furthermore, an improved method of rotating the potential trap to generate vortex is proposed. Quantum gyroscope based on BEC vortex has the potential advantages of realizing the ultra high sensitivity and small volume of quantum gyroscope. This paper aims to promote the development of quantum vortex gyroscope, which attracts extensive attention of domestic scholars.
The exchange of orbital angular momentum (OAM) between paraxial optical vortex and a Bose-Einstein condensate (BEC) of atomic gases is well known. In this paper, we develop a theory for the microscopic interaction between matter and an optical vortex beyond paraxial approximation. We show how superposition of vortex states of BEC can be created with a focused optical vortex. Since the polarization or spin angular momentum (SAM) of the optical field is coupled with OAM of the field, in this case, these angular momenta can be transferred to the internal electronic and external center-of-mass motion of atoms provided both the motions are coupled. We propose a scheme for producing the superposition of matter-wave vortices using Gaussian and a focused Laguerre-Gaussian beam. We study how two-photon Rabi frequencies of stimulated Raman transitions vary with focusing angles for different combinations of OAM and SAM of optical states. We demonstrate the formation of vortex-antivortex structure and discuss interference of three vortex states in a BEC.