Torsion method for measuring piezooptic coefficients

Abstract

We develop and describe analytically a torsion method for measuring piezooptic coefficients associated with shear stresses. It is shown that the method enables to increase significantly the accuracy of determination of piezooptic coefficients. The method and the appropriate apparatus are verified experimentally on the example of LiNbO 3 crystals.

Measurements of piezooptic coefficients pi(14) and pi(25) in Pb5Ge3O11 crystals using torsion induced optical vortex

“…Recently we have suggested a new high-accuracy torsion method for studies of piezooptic effect in solids [1][2][3][4][5]. As shown in our works, the method generally provides fairly high accuracy for piezooptic coefficients.…”

“…As shown in our works, the method generally provides fairly high accuracy for piezooptic coefficients. In particular, the error for so-called non-principal coefficients has been reduced to a few percents [2,3] (Concerning the piezooptic effect itself, we refer reader to Ref. [6]).…”

“…[6]). As a result, we have successfully determined the piezooptic coefficient π 14 for LiNbO 3 crystals belonging to the point symmetry group 3m and α-BaB 2 O 4 crystal (the point group 3m ) [2][3][4]. It has been demonstrated that the sign of the piezooptic coefficients, e. g. the coefficient π 14 , can also be determined using the torsion method [4].…”

Efficiency of spin-to-orbit conversion in crystals subjected to torsion stresses

“…Following from this condition, we have studied the crystals belonging to the above point symmetry groups, for which the necessary piezooptic parameters are known form the literature. For our best knowledge, LiNbO 3 [5], α-BaB 2 O 4 [6] and β-BaB 2 O 4 [7], quartz [8], hexamethylenetetramine [9], NaCl, KAl(SO 4 …”

Refined measurements of piezooptic coefficient pi66 for the lithium niobate crystals, using a crystalline disk compressed along its diameter

“…They make use of the loading methods which give rise to non-uniform, though known in advance, stress distributions in a sample. These are a measuring technique based on crystal torsion [12][13][14], a combination of digital imaging laser interferometry with a classical four-point bending method [15][16][17], and a technique based on compressing of crystalline disks along their diameters [18].…”