In Concentration Dependence of Shallow Impurity Binding Energy Under The Hydrostatic Pressure

Yıl 2011, Cilt: 23 Sayı: 4, 171 - 180, 01.04.2012

Pınar Baser , İsmail Altuntas Sezai Elagoz

Öz

The ground state binding energy of axial hydrogenic impurity in zinc-blende (ZB) In_xGa_1-xN/GaN cylindrical quantum well wires( CQWWs) are investigated as a function of the In concentration and the radius of the wire under hydrostatic pressure in the effective mass approximation and variational calculation scheme. The effect of applied hydrostatic pressure is introduced into the calculations using pressure dependent values of energy band gap and effective mass. Numerical results show that the ground-state shallow impurity binding energy E_b altered when both the hydrostatic pressure and In concentration increases for an on-center impurity. We have found that for large radii the binding energies are not affected by applied pressure. However, in the region where the particles interact with the barrier the binding energy is strongly dependent on the hydrostatic pressure for all x values. Furthermore, we have seen that the binding energy of the shallow impurity is affected more by the change of In concentration compared to the change of hydrostatic pressure.

Anahtar Kelimeler

Quantum wires; Binding energy; Hydrostatic pressure; In concentration

Sığ Safsızlık Bağlanma Enerjisinin Hidrostatik Basınç Altında In Konsantrasyonuna Bağlılığı

Öz

Çinko sülfür InxGa1-xN/GaN silindirik kuantum telindeki (CQWWs) hidrojenik safsızlık taban durum bağlanma
enerjisi, hidrostatik basınç altında In konsantrasyonu ve tel yarıçapının fonksiyonu olarak etkin kütle yaklaşımı
ve varyasyonel teknikler kullanılarak incelendi. Uygulanan hidrostatik basınç etkisi, yasak enerji aralığı, tel
yarıçapı ve etkin kütlenin basınca bağlılığı kullanılarak hesaplamalara katıldı. Hesaplamaların bağlanma enerjisi
Eb’ nin merkezdeki bir safsızlık için hem hidrostatik basınç hem de In konsantrasyonu arttırıldığında, bu
parametrelere bağlı olarak değiştiğini gösterdi. Çok büyük tel yarıçaplarında bağlanma enerjisinin basınçtan
etkilenmediği, Ancak parçacıkların engellerle etkileşmeye başladığı tel yarıçaplarında bağlanma enerjisi bütün x
değerleri için hidrostatik basınca bağlı olduğu gözlendi. Ayrıca, In konsantrasyonunun ve hidrostatik basıncın
bağlanma enerjisine etkisi karşılaştırıldığında In konsantrasyonundan kaynaklanan etkinin daha güçlü olduğu
bulundu

Anahtar Kelimeler

Kuantum teli, Bağlanma enerjisi, Hidrostatik basınç, In konsantrasyonu.

Kaynakça

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