High birefringence of the yttrium vanadate crystal in the middle wavelength infrared

Abstract

A high birefringence of over 0.21 for the yttrium vanadate (YVO4) crystal in the middle wavelength infrared (i.e., 3-5 microm) was measured. A Fourier transform infrared spectrometer was employed in the channel spectra technique to obtain the measurements.

An Exceptional Peroxide Birefringent Material Resulting from d–π Interactions

“…According to the first-principles calculations, this exceptional birefringence should be attributed to the strong electronic interactions between localized p orbital of O 2 2À anions and V 5+ 3d orbitals, which may be also favorable to the stability in the air for Rb 2 VO(O 2 ) 2 F. These findings distinguish peroxides as a brand-new class of birefringent materials that may possess birefringence superior to the traditional oxides.Birefringent materials can modulate the polarization of light, which is among the most interesting phenomena in nature and has resulted in a lot of discoveries, and thus they have attracted a lot of commercial and academic interest in many scientific and engineering branches. [1] Over the past decades, scientists have made continuous intense studies, thereby leading to a variety of commercial birefringent crystals including YVO 4 , [2] LiNbO 3 , [3] rutile (TiO 2 ), [4] calcite (CaCO 3 ), [5] and a-BaB 2 O 4 , [6] which are widely used in optical devices, such as optical isolators, circulators, beam displacers, and phase compensators. [7] Nevertheless, natural birefringent crystals (such as calcite [5] and rutile [4] ) have limited applications because of their poor crystal quality and various geological impurities, while artificial birefringent crystals (for example, YVO 4 , [2] LiNbO 3 , [3] a-BaB 2 O 4[6] ) are relatively expensive and it is energy-consuming to grow their single crystals.…”

“…[1] Over the past decades, scientists have made continuous intense studies, thereby leading to a variety of commercial birefringent crystals including YVO 4 , [2] LiNbO 3 , [3] rutile (TiO 2 ), [4] calcite (CaCO 3 ), [5] and a-BaB 2 O 4 , [6] which are widely used in optical devices, such as optical isolators, circulators, beam displacers, and phase compensators. [7] Nevertheless, natural birefringent crystals (such as calcite [5] and rutile [4] ) have limited applications because of their poor crystal quality and various geological impurities, while artificial birefringent crystals (for example, YVO 4 , [2] LiNbO 3 , [3] a-BaB 2 O 4[6] ) are relatively expensive and it is energy-consuming to grow their single crystals. Therefore, there is still great demand for outstanding birefringent materials for which it is facile to grow single crystals.It is well-known that birefringence is closely related to the anisotropic polarizability of a structure.…”

“…[8] Large anisotropic polarizability in crystals will give rise to large birefringence. Some strategies have been developed to enhance the birefringence of a crystal: 1) Introducing second-order Jahn-Teller distorted polyhedra with d 0 cation (V 5+ , Mo 6+ ) centers; [9] related compounds include YVO 4 (Dn = 0.225 at 633 nm) [2] and NaCa 4 V 5 O 17 (Dn = 0.1 at 1064 nm); [10] 2) introduction or condensation of delocalized p-conjugated planar groups such as BO 3 groups; for example, Pan and co-authors recently reported two borates, Li 2 Na 2 B 2 O 5[8b] and CaB 2 O 4 , [8a] which are composed of condensed B 2 O 5 dimers and [B 2 O 4 ] 1 infinite chains and exhibit large birefringences of Dn = 0.095 at 532 nm and Dn = 0.1355 at 546 nm, respectively; 3) introducing highly polarizable cations such as Hg 2+ with d 10configuration or Pb 2+ , Sn 2+ , I 5+ with lone pair electrons as in LiHgPO 4 (Dn = 0.068 at 1064 nm), [11] Pb 2 (IO 3 )(PO 4 ) (Dn = 0.060 at 1064 nm), [12] and Sn 2 B 5 O 9 Cl (Dn = 0.168 at 546 nm). [13] In particular, Sn 2 B 5 O 9 Cl [13] exhibits a remarkable enhancement of 16 times as compared with the isostructural Ba 2 B 5 O 9 Cl.…”

“…[8] Large anisotropic polarizability in crystals will give rise to large birefringence. Some strategies have been developed to enhance the birefringence of a crystal: 1) Introducing second-order Jahn-Teller distorted polyhedra with d 0 cation (V 5+ , Mo 6+ ) centers; [9] related compounds include YVO 4 (Dn = 0.225 at 633 nm) [2] and NaCa 4 V 5 O 17 (Dn = 0.1 at 1064 nm); [10] 2) introduction or condensation of delocalized p-conjugated planar groups such as BO 3 groups; for example, Pan and co-authors recently reported two borates, Li 2 Na 2 B 2 O 5…”

“…Yellow plate-like crystals of Rb 2 VO(O 2 ) 2 F (Supporting Information, Figure S1) were synthesized by a facile aqueous solution method. V 2 (1 mmol) and RbF (20 mmol) was dissolved in H 2 O 2 (5 mL) and H 2 O (5 mL) in a beaker. The resulting yellow solution was then transferred to a refrigerator and slowly evaporated at 277 K. Yellow plate-like crystals were grown in about 20 days.…”