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Nematic-Orbit Coupling and Nematic Density Waves in Spin-1 Condensates
Di Lao1, Chandra Raman1, C A R Sá de Melo1
1School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
Physical Review Letters
|May 16, 2020
Summary
Researchers created artificial nematic-orbit coupling in spin-1 Bose-Einstein condensates using microwave chips. This method allows manipulation of tensorial degrees of freedom in ultracold gases, avoiding laser-induced heating.
Area of Science:
- Atomic, Molecular, and Optical Physics
- Quantum Gases
- Condensed Matter Theory
Background:
- Spin-orbit coupling is crucial for understanding many quantum phenomena.
- Controlling tensorial degrees of freedom in ultracold gases is experimentally challenging.
- Existing methods often involve Raman lasers, leading to unwanted heating.
Purpose of the Study:
- To propose and theoretically investigate artificial nematic-orbit coupling in spin-1 Bose-Einstein condensates.
- To explore quantum phases and excitation spectra arising from this novel coupling.
- To demonstrate a method for manipulating tensorial properties without Raman lasers.
Main Methods:
- Utilizing a designed microwave chip to create a spatiotemporally varying quadratic Zeeman shift.
- Analyzing the phase diagram of the system, identifying distinct quantum phases with nematic order.
- Calculating low-energy excitation spectra considering spin-dependent and spin-independent interactions.
Main Results:
- Three distinct quantum phases with nematic order were identified: easy axis, easy plane with single-well, and easy plane with double-well structures.
- The low-energy excitation spectra for these phases were derived.
- A periodic nematic density modulation was shown to arise from the nematic-orbit coupling.
Conclusions:
- Artificial nematic-orbit coupling offers a new pathway for controlling tensorial degrees of freedom in ultracold gases.
- The proposed microwave chip method circumvents the heating issues associated with Raman lasers.
- This work opens avenues for novel quantum simulations and applications in quantum information processing.
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