Application of a rotating heat field in Bridgman–Stockbarger crystal growth

Кох, К. А.; Nenashev, B. G.; Kokh, A. E.; Shvedenkov, G. Yu.

doi:10.1016/j.jcrysgro.2004.11.299

Cited by 61 publications

(36 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We demonstrated that application of a rotating heat field 33 helps considerably in resolving this problem. As a result, a set of GaSe crystals with sub-orthogonal orientation of the cleavage plane to the growth axis was obtained [34][35][36] .…”

Section: Crystal Growth and Sample Fabricationmentioning

confidence: 99%

Doped GaSe crystals for laser frequency conversion

Guo

Xie

et al. 2015

Light Sci Appl

View full text Add to dashboard Cite

In this review, we introduce the current state of the art of the growth technology of pure, lightly doped, and heavily doped (solid solution) nonlinear gallium selenide (GaSe) crystals that are able to generate broadband emission from the near infrared (IR) (0.8 mm) through the mid-and far-IR (terahertz (THz)) ranges and further into the millimeter wave (5.64 mm) range. For the first time, we show that appropriate doping is an efficient method controlling a range of the physical properties of GaSe crystals that are responsible for frequency conversion efficiency and exploitation parameters. After appropriate doping, uniform crystals grown by a modified technology with heat field rotation possess up to 3 times lower absorption coefficient in the main transparency window and THz range. Moreover, doping provides the following benefits: raises by up to 5 times the optical damage threshold; almost eliminates two-photon absorption; allows for dispersion control in the THz range independent of the mid-IR dispersion; and enables crystal processing in arbitrary directions due to the strengthened lattice. Finally, doped GaSe demonstrated better usefulness for processing compared with GaSe grown by the conventional technology and up to 15 times higher frequency conversion efficiency. INTRODUCTIONThe e-polytype of gallium selenide (hereinafter GaSe) has been known since 1934 1 and promises efficient optical frequency conversion and detection over a large range of wavelengths. The performance potential of GaSe, which belongs to the point group symmetry 6m2, can be attributed to its extreme physical properties. GaSe has a broadband transparency window over the range of 0.62-20 mm for non-polarized light continues at wavelengths o50 mm 2,3 . Other attractive physical properties of GaSe are its prodigious birefringence B 5 0.375 at l 5 10.6 mm and 0.79 at terahertz (THz) range 4 , and very high second-order nonlinear susceptibility d 22 5 54 pm V 21 at 10 mm 5 and 24.3 pm/V in the THz band 6 . Among the mid-infrared (IR) anisotropic nonlinear crystals, GaSe has the second highest optical damage threshold 7,8 and thermal conductivity in the plane of the (0001) A GaSe crystal was first used for laser frequency conversion in the mid-IR in 1972 9,10 . In subsequent years, GaSe was widely used for inlab mid-IR applications 5 . Over the past two decades, GaSe has been among the most promising nonlinear optical crystals for efficient generation of ultrabroadband radiation 0.8-5640 mm (with the

show abstract

Section: Crystal Growth and Sample Fabricationmentioning

confidence: 99%

Doped GaSe crystals for laser frequency conversion

Guo

Xie

et al. 2015

Light Sci Appl

View full text Add to dashboard Cite

show abstract

“…Part of these experiments were carried out at the Research Resource Center of Saint Petersburg State University "Physical methods of surface investigation" using the same detection geometry in combination with a monochromatized discharge He-lamp providing 21.2-eV photons. In these experiments, a slightly The n-doped samples with stoichiometry of Bi 2 Te 2.4 Se 0.6 were grown from a previously synthesized mixture of Bi 2 Te 3 and Bi 2 Se 3 compounds using a modified vertical Bridgman method [34]. Before measurements, the samples were cleaved in situ at room temperature in ultrahigh vacuum.…”

Section: Experimental and Computational Detailsmentioning

confidence: 99%

Electronic and spin structure of the topological insulator Bi2Te2.4Se0.6

et al. 2014

View full text Add to dashboard Cite

High-resolution spin-and angle-resolved photoemission spectroscopy measurements were performed on the three-dimensional topological insulator Bi 2 Te 2.4 Se 0.6 , which is characterized by enhanced thermoelectric properties. The Fermi level position is found to be located in the bulk energy gap independent of temperature and it is stable over a long time. Spin textures in the Dirac-cone state at energies above and below the Dirac point as well as in the Rashba-type valence band surface state are observed in agreement with theoretical prediction. The calculations of the surface electronic structure demonstrate that the fractional stoichiometry induced disorder within the Te/Se sublattice does not influence the Dirac-cone state dispersion. In spite of relatively high resistivity, temperature dependence of conductivity shows a weak metallic behavior that could explain the effective thermoelectric properties of the Bi 2 Te 2.4 Se 0.6 compound with the in-plane Seebeck coefficient reaching −330 μV/K at room temperature.

show abstract

“…The Bi 2 Te 2 Se crystal was grown by the modified vertical Bridgman method as described elsewhere. 28 The STM images were obtained in a constant-current mode, and the differential conductance dI/dV maps were measured simultaneously with recording the STM images using a standard lock-in technique. ARPES experiments were conducted using the synchrotron radiation at the beamline (BL-7) equipped with a hemispherical photoelectron analyzer (VG-SCIENTA SES2002) of the Hiroshima Synchrotron Radiation Center (HSRC).…”

mentioning

confidence: 99%

Unoccupied topological surface state in Bi2Te2Se

et al. 2013

View full text Add to dashboard Cite

Bias voltage dependent scattering of the topological surface state is studied by scanning tunneling microscopy/spectroscopy for a clean surface of the topological insulator Bi 2 Te 2 Se. A strong warping of constant energy contours in the unoccupied part of the spectrum is found to lead to a spin-selective scattering. The topological surface state persists to higher energies in the unoccupied range far beyond the Dirac point, where it coexists with the bulk conduction band. This finding sheds light on the spin and charge dynamics over a wide energy range and opens a way to designing optospintronic devices.

show abstract

Application of a rotating heat field in Bridgman–Stockbarger crystal growth

Cited by 61 publications

References 9 publications

Doped GaSe crystals for laser frequency conversion

Doped GaSe crystals for laser frequency conversion

Electronic and spin structure of the topological insulator Bi2Te2.4Se0.6

Unoccupied topological surface state in Bi2Te2Se

Contact Info

Product

Resources

About