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Ferromagnetic Ising Spin Chains Emerging from the Spin Ice under Magnetic Field

Zenji Hiroi·Kazuyuki Matsuhira·Masao Ogata
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Abstract

A spin-ice compound dysprosium titanate, Dy2Ti2O7, is studied by specific heat measurements in magnetic fields applied along the [110] direction of the cubic unit cell. Above a magnetic field of 0.4 T a relatively sharp peak at T = 1.1 K in the specific heat appears from a broad peak associated with spin-ice freezing at low fields. This new peak is almost independent of field up to 1.5 T, while another broad, field-dependent peak is detected at higher temperature. Under magnetic field along [110] Ising spins on the pyrochlore lattice can be considered to form two orthogonal sets of chains; parallel and perpendicular to the field direction. It is suggested that these perpendicular chains behave as unique ferromagnetic Ising spin chains without long-range order.

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Zenji Hiroi, Kazuyuki Matsuhira, Masao Ogata. 2003-09-19. Ferromagnetic Ising Spin Chains Emerging from the Spin Ice under Magnetic Field. https://doi.org/10.1143/jpsj.72.3045

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