ISSN 1330–0008 CODEN FIZAE4 LETTER TO THE EDITOR ANOMALOUS MAGNETORESISTANCE OF SINGLE CRYSTALS OF DOPED BISMUTH DIPALI BANERJEE a , RAMENDRANARAYAN BHATTACHARYA b, 1 and KUSHALENDU GOSWAMI c a Department of Physics, B. E. College (D. U.), Howrah 711103, India b Solid State Physics, Indian Association for the Cultivation of Science, Jadavpur, Calcutta 700032, India c Department of Physics, Jadavpur University, Jadavpur, Calcutta 700032, India Received 2 December 1999 ; revised manuscript received 18 August 2000 Accepted 23 October 2000 Measurements of magnetoresistance of single crystals of bismuth doped with tin and lead in the temperature range 100 K to 300 K are reported. Both tin and lead have a marked effect in changing the band structure of bismuth. Temperature variations show that with the increased concentration of impurity, Δρ/ρ 0 is less de- pendent on temperature, and the magnetic field variation of Δρ/ρ 0 does not obey the quadratic dependence on magnetic field strength. PACS numbers: 75.20.Ck UDC 537.621.2, 537.622 Keywords: magnetoresistance, single crystals of bismuth doped with tin and lead, temper- ature and the magnetic field variation, deviation from quadratic dependence on magnetic field strength Bismuth exhibits a number of very interesting transport properties due to the presence of its overlapping bands [1–5]. Doped-bismuth materials show interest- ing variations of galvanomagnetic properties [6,7]. For example, variation of the Hall coefficient of doped bismuth with magnetic field at steady temperature shows that the Hall coefficient undergoes a change of sign from negative to positive [7]. Therefore, we decided to investigate whether the magnetoresistance also shows an unusual variation with magnetic field. We found no such previous report. 1 Author for correspondence, e-mail: lipida@hotmail.com FIZIKA A (Zagreb) 9 (2000) 4, 153–158 153