Anomalous increase of the thermopower and thermoelectric figure of merit in Ga-doped p-(Bi0.5Sb0.5)2Te3 single crystals

Kulbachinskii, V. A.; Кытин, В. Г.; Tarasov, P. M.; Yuzeeva, N. A.

doi:10.1134/s1063783410090076

Cited by 17 publications

(9 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As far as literature reports are concerned, two works 54,55 reported anomalous increase of the thermopower and ZT in Ga-doped n-type (Bi 0:5 Sb 0:5 ) 2 Te 3 alloy, which may be due to RL formation. Results of the calculations for the series of Al-and Ga-doped materials are presented in Figs.…”

Section: Al and Ga: Possible New Resonant Impuritiesmentioning

confidence: 99%

Resonant Levels, Vacancies, and Doping in Bi2Te3, Bi2Te2Se, and Bi2Se3 Tetradymites

Wiendlocha

2016

Journal of Elec Materi

View full text Add to dashboard Cite

3 . Vacancies, which are likely present on chalcogen atom sites in real samples of Bi 2 Te 2 Se and Bi 2 Se 3 , are also studied and their charged donor and resonant behavior discussed. Doping of vacancycontaining materials with regular acceptors, such as Ca or Mg, is shown to compensate the donor effect of vacancies, and n À p crossover, while increasing the dopant concentration, is observed. We verify that the RL on Sn is not disturbed by chalcogen vacancies in Bi 2 Te 2 Se or Bi 2 Se 3 , and for the Sn-doped materials with Se or Te vacancies, double doping, instead of heavy doping with Sn, is suggested as an effective way of obtaining the resonant level. This should help to avoid smearing of the RL, a possible reason for earlier unsuccessful experimental observation of the influence of the RL on the thermoelectric properties of Sn-doped Bi 2 Te 2 Se. Finally, we show that Al and Ga are possible new resonant impurities in tetradymites, hoping that this will stimulate further experimental studies.

show abstract

Section: Al and Ga: Possible New Resonant Impuritiesmentioning

confidence: 99%

Resonant Levels, Vacancies, and Doping in Bi2Te3, Bi2Te2Se, and Bi2Se3 Tetradymites

Wiendlocha

2016

Journal of Elec Materi

View full text Add to dashboard Cite

show abstract

“…1b. Likewise, we illustrate the bulk band structure consisting of two hole bands offset from the Γ point, with an electron band at the Γ point, as measured previously [10,12,15]. The relative positioning of E F , the Dirac point, and bulk bands that we propose has been observed in similar, albeit more highly doped, (Bi 1−x Sb x ) 2 Te 3 thin films [12].…”

mentioning

confidence: 82%

“…Alternatively, we considered the case that the optical response arises from the bulk valence bands. Prior work has shown that the bulk valence band structure in the (Bi,Sb) 2 Te 3 system consist of of a light hole band (LHB) and heavy hole band (HHB) [3,14,15]. The effective masses of LHB and the HHB are 0.11m e and 1.0 m e respectively, and the top of the HHB is approximately 30 meV below the LHB [14,15].…”

mentioning

confidence: 99%

“…Prior work has shown that the bulk valence band structure in the (Bi,Sb) 2 Te 3 system consist of of a light hole band (LHB) and heavy hole band (HHB) [3,14,15]. The effective masses of LHB and the HHB are 0.11m e and 1.0 m e respectively, and the top of the HHB is approximately 30 meV below the LHB [14,15]. To recover the correct value of D for this sample, E F would be 30 meV below the top of the LHB, However, this would yield an n 2D of 5 × 10 12 cm −2 , over a factor of two smaller than what was measured.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Sum-Rule Constraints on the Surface State Conductance of Topological Insulators

et al. 2015

View full text Add to dashboard Cite

“…It is proposed that In substitution at Bi site in Bi 0.5 Sb 1.5 Te 3 increases the bond polarity and increases the energy for Bi/Sb atom to migrate to Te position, thereby suppresses antisite defect formation [4]. [6] that Ga doping in Bi 0.5 Sb 1.5 Te 3 results in anomalous increase in Seebeck coefficient and thermoelectric figure of merit at 300K. It was recently shown by Kulbachinskii et.al.…”

Section: Introductionmentioning

confidence: 99%

Effect of Sn Substitution on the Thermoelectric Properties of Nanostructured Bulk Bi_2-xSb_xTe₃ Alloy.

et al. 2011

View full text Add to dashboard Cite

The carrier concentration and electronic transport properties in Bi 2-x Sb x Te 3 alloy can be tuned by varying the Bi to Sb ratio, for high thermoelectric figure of merit. The concentration of intrinsic antisite defects in these alloys is also known to change with Bi to Sb ratio. Here we report the thermoelectric figure of merit of Sn doped Bi 0.5 Sb 1.5 Te 3 alloy. Different atomic percentages of Sn was substituted at Bi/Sb site in Bi 0.5 Sb 1.5 Te 3 alloy, synthesized by planetary ball milling. The electrical conductivity decreases with increasing Sn doping but for higher Sn content the electrical conductivity increases compared to undoped alloy. The Seebeck coefficient changes in accordance to electrical conductivity, resulting in small decrease in power factor for highest Sn doping. The lattice thermal conductivity shows a systematic decrease, with increasing Sn concentration resulting in a significant thermal conductivity reduction. Hence an increase in thermoelectric figure of merit could be achieved for the highest Sn (3at%) doping in Bi 0.5 Sb 1.5 Te 3 alloy as compared to undoped alloy.

show abstract

Anomalous increase of the thermopower and thermoelectric figure of merit in Ga-doped p-(Bi0.5Sb0.5)2Te3 single crystals

Cited by 17 publications

References 11 publications

Resonant Levels, Vacancies, and Doping in Bi2Te3, Bi2Te2Se, and Bi2Se3 Tetradymites

Resonant Levels, Vacancies, and Doping in Bi2Te3, Bi2Te2Se, and Bi2Se3 Tetradymites

Sum-Rule Constraints on the Surface State Conductance of Topological Insulators

Effect of Sn Substitution on the Thermoelectric Properties of Nanostructured Bulk Bi_2-xSb_xTe₃ Alloy.

Contact Info

Product

Resources

About

Anomalous increase of the thermopower and thermoelectric figure of merit in Ga-doped p-(Bi0.5Sb0.5)2Te3 single crystals

Cited by 17 publications

References 11 publications

Resonant Levels, Vacancies, and Doping in Bi2Te3, Bi2Te2Se, and Bi2Se3 Tetradymites

Resonant Levels, Vacancies, and Doping in Bi2Te3, Bi2Te2Se, and Bi2Se3 Tetradymites

Sum-Rule Constraints on the Surface State Conductance of Topological Insulators

Effect of Sn Substitution on the Thermoelectric Properties of Nanostructured Bulk Bi2-xSbxTe3 Alloy.

Contact Info

Product

Resources

About

Effect of Sn Substitution on the Thermoelectric Properties of Nanostructured Bulk Bi_2-xSb_xTe₃ Alloy.