Optical anisotropic-dielectric response of mercuric iodide

Journal Article · Wed Oct 01 04:00:00 EDT 1997 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.56.9414· OSTI ID:543816

Yao, H ^[1]; Johs, B ^[2]; James, R B ^[3]

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1. Center for Microelectronic and Optical Materials Research and Department of Electrical Engineering, University of Nebraska, Lincoln, Nebraska 68588-0511 (United States)
2. J. A. Woollam Company, Inc., Lincoln, Nebraska 68508 (United States)
3. Sandia National Laboratories, Livermore, California 94551-0969 (United States)

Anisotropic optical properties of mercuric iodide (HgI{sub 2}) were studied by variable-angle spectroscopic ellipsometry (VASE). Angular-dependent polarized reflectance and transmittance at three special optical-axis configurations, concerning the uniaxial anisotropic nature of the crystal, were derived to facilitate the VASE analysis. Two surface orientations of this tetragonal crystal were selected, i.e., an a-plane and a c-plane sample. Room-temperature multiple-angle spectroscopic ellipsometry measurements from both samples with three different optical configurations along with polarized transmission measurements were jointly analyzed by the VASE analysis through multiple-sample, multiple-model methods. Anisotropic dielectric functions of single-crystal HgI{sub 2}, {var_epsilon}{sub {perpendicular}}({omega}) and {var_epsilon}{sub {parallel}}({omega}), for optical electric-field vector oriented perpendicular and parallel to the c axis, respectively, were obtained in the range 1.24{endash}5.1 eV. Different absorption energy-band edges, at room temperature, were observed from the ordinary and extraordinary dielectric responses at 2.25 and 2.43 eV, respectively. This is consistent with the results related to the optical transitions between the conduction band and the heavy- and light-hole valence band indicated by theoretical studies. A surface model related to the surface roughness and defects of HgI{sub 2} was established and characterized by the VASE analysis. {copyright} {ital 1997} {ital The American Physical Society}

• OSTI ID: 543816
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 15 Vol. 56; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ABSORPTION SPECTRA
CRYSTAL DEFECTS
DIELECTRIC TENSOR
ELLIPSOMETRY
LIGHT TRANSMISSION
MERCURY COMPOUNDS
MERCURY IODIDES
OPTICAL PROPERTIES
OPTICAL REFLECTION
REFLECTIVITY
SEMICONDUCTOR MATERIALS