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arXiv · 0803.2815

Magnetic field-induced one-magnon Raman scattering in the magnon Bose-Einstein condensation phase of TlCuCl$_{3}$

Haruhiko Kuroe·Kouhei Kusakabe·Akira Oosawa·Tomoyuki Sekine·Fumiko Yamada·Hidekazu Tanaka·Masashige Matsumoto
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Abstract

We report the observation of the $A_{\rm g}$-symmetric one-magnon Raman peak in the magnon Bose-Einstein condensation phase of TlCuCl$_{3}$. Its Raman shift traces the one-magnon energy at the magnetic $Γ$ point, and its intensity is proportional to the squared transverse magnetization. The appearance of the one-magnon Raman scattering originates from the exchange magnon Raman process and reflects the change of the magnetic-state symmetry. Using the bond-operator representation, we theoretically clarify the Raman selection rules, being consistent with the experimental results.

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Haruhiko Kuroe, Kouhei Kusakabe, Akira Oosawa, Tomoyuki Sekine, Fumiko Yamada, Hidekazu Tanaka, Masashige Matsumoto. 2008-03-19. Magnetic field-induced one-magnon Raman scattering in the magnon Bose-Einstein condensation phase of TlCuCl$_{3}$. https://doi.org/10.1103/physrevb.77.134420

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