Skyrmion Liquid Phase of the Quantum Ferromagnet in Two Dimensions
نویسنده
چکیده
The two-dimensional quantum ferromagnet filled with a liquid of skyrmions is studied theoretically in the context of the quantum Hall effect near electronic filling factor ν = 1. A cross-over between the classical ferromagnetic phase at ν = 1 and a classical paramagnetic phase at ν 6= 1 is obtained, which is consistent with recent Knight-shift measurements. A new collective mode associated with the skyrmion liquid that is of the cyclotron type is also identified. PACS Indices: 73.40.Hm, 75.10.Jm, 75.40.Cx * Permanent address.
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تاریخ انتشار 1996