  Metal/superconductor/semiconductor (Ag/HgBaCaCuO/CdSe) heterostructures have
been successfully fabricated using pulse-electrodeposition technique. The
electrochemical parameters are optimized and diffusion free growth of CdSe onto
Ag/HgBaCaCuO was obtained by employing under-potential deposition and by
studying nucleation and growth mechanism during deposition. The
heterostructures are characterized by X-ray diffraction (XRD), full-width at
half-maximum (FWHM), scanning electron microscopy (SEM) studies and low
temperature four probe electrical resistivity measurements. After the
deposition of CdSe the critical transition temperature of HgBaCaCuO films was
found be increased from 115 K with Jc = 1.7 x 103 A/cm2 to 117.2 K with Jc =
1.91 x 103 A/cm2. When the heterostructure was irradiated with red He-Ne laser
(2 mW), the Tc was further enhanced to 120.3 K with Jc = 3.7 x 103 A/cm2. This
increase in superconducting parameters of HgBaCaCuO in Ag/ HgBaCaCuO/CdSe
heterostructure has been explained at length in this paper.
  Keywords. Electrodeposition; Hg-based cuprate; semiconductor;
heterostructures; electrical properties.
  PACS Nos 81.15.Pq; 74.72.Gr; 78.40.Fy; 84.37; 73.40 *E-mail:
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