No abstract

Large TlInSe2 single crystals are grown by the Bridgman‐Stockbarger method, starting from stoichiometric melts. Current–voltage (I–V) characterstics of symmetric In/p‐TlInSe2/In structures exhibit two distinct regions: an ohmic region at low current densities and a non‐linear region (S‐shaped) having negative differential resistance (NDR) at moderate and higher current densities. An electrothermal model is used for the explanation of this non‐linear behaviour. The non‐linear behaviour of the I–V curves is studied at different ambient temperatures in the 100 to 340 K region. The sample temperature and the threshold voltage of the NDR region are examined as a function of current density and ambient temperature, respectively. The electrothermal model is quite satisfactory for the explanation of this process.

No abstract

The temperature dependence of the transverse magnetoresistance in irradiated and unirradiated p‐type Si is studied in the range from 120 to 290 K. The magnetoresistance coefficients for the unirradiated [001] and [110] samples increases with decreasing sample temperature in the range from 160 to 290 K, however, this behavior is reversed below 160 K. It is proposed that this reversal is due to the double injection effect. The magnetoresistance coefficient for the irradiated [100] sample increases with decreasing sample temperature in the range of 120 to 290 K and is greater than that for the unirradiated [001] sample. This result can be explained by increased scattering due to the increased number of defects produced by irradiation. On the other hand, the magnetoresistance coefficient for the unirradiated [110] sample is found to be greater than that of the unirradiated [001] sample.