On isotropic states in α-LiNH4SO4 crystals


The spectral and baric dependences of the birefringence of α-LiNH4SO4 crystals are studied. It is found that the birefringence is rather sensitive to uniaxial compressions. A baric shift of the isotropic point to longer or shorter wavelengths depending on the uniaxial compression direction is observed and a generalized temperature-spectral-baric diagram of the isotropic state is plotted. A possibility of the appearance of a pseudoisotropic state under the action of uniaxial pressure σ z or simultaneous pressures σ x = σ z is shown.

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Correspondence to V. Yo. Stadnyk.

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Original Russian Text © V.Yo. Stadnyk, R.S. Brezvin, M.Ya. Rudysh, P.A. Shchepanskyi, V.M. Gaba, Z.A. Kogut, 2014, published in Optika i Spektroskopiya, 2014, Vol. 117, No. 5, pp. 779–782.

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Stadnyk, V.Y., Brezvin, R.S., Rudysh, M.Y. et al. On isotropic states in α-LiNH4SO4 crystals. Opt. Spectrosc. 117, 756–758 (2014). https://doi.org/10.1134/S0030400X14110216

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  • Uniaxial Compression
  • Isotropic State
  • Isotropic Point
  • Uniaxial Pressure
  • Baric Diagram