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p theory. Phys. Rev. B 59, 5688–5701 (1999)Stock, E., Warming, T., Ostapenko, I., Rodt, S., Schliwa, A., Tofflinger, ., Lochmann, A., Toropov, .,Moshchenko, ., Dmitriev, ., Haisler, ., Bimberg, D.: Singlephoton emission from InGaAsquantum dots grown on (111) GaAs. Appl. Phys. Lett. 96, 093112–093114 (2010)Zhao, Q., Mei, T.: J. Appl. Phys. 109, 063101–063113 (2011)Zhu, Q., Karlsson, ., Pelucchi, E., Kapon, E.: Transition from twodimensional to threedimensional quantum con?nement in semiconductor quantum wires/quantum dots. Nano Lett. 7, 2227–2233 (2007)123。 p formalism and continuum elasticity theory. Comput. Phys. Commun. 181, 765–771 (2010)Marquardt, O., Freysoldt, C., Boeck, S., Hickel, T., Neugebauer, J.: to be submittedMarquardt, O., Mourad, D., Schulz, S., Hickel, T., Czycholl, G., Neugebauer, J.: Comparison of atomistic andcontinuum theoretical approaches to determine electronic properties of GaN/AlN quantum dots. Phys.Rev. B 78, 235302–235310 (2008)Marquardt, O., O’Reilly, ., Schulz, S.: to be submittedMereni, ., Dimastrodonato, V., Young, ., Pelucchi, E.: A sitecontrolled quantum dot system offeringboth high uniformity and spectral purity. Appl. Phys. Lett. 94, 223121–223123 (2009)Pfeffer, P., Zawadzki, W.: Fivelevel k p perturbation theory in IIIV pounds and alloys: a reexamination. Phys.Rev. B 15, 823–833 (1977)Healy, ., Young, ., Mereni, ., Dimastrodonato, V., Pelucchi, E., O’Reilly, .: Physics of novel sitecontrolled InGaAs quantum dots on (111) oriented substrates. Physica E 42, 2761–2764 (2009)Jancu, ., Scholz, R., De Andrada e Silva, ., La Rocca, .: Atomistic spinorbit coupling and k ReferencesBahder, T.: Eightband k 上面的例子表明了我們廣義的和有效率的多波段KP模型。P模型做一個比較,可以重現(xiàn)P態(tài)分裂在錐體的InAs量子點,通過采用反映了ZB晶格正確的對稱性的14波段模型NXP模型的方法一個可以用來研究廣泛的半導(dǎo)體納米結(jié)構(gòu)的電子特性。 p model.123O. Marquardt et al.This symmetryadapted model allows for a description of (111)oriented nanostructures witha significantly smaller putational effort than using a conventional eightband Hamiltonian. The above examples demonstrate the high ?exibility and ef?ciency of our generalisedmultiband k p approach which can be used to studythe electronic properties of a wide range of semiconductor nanostructures. The implementation of this model in a PW framework in the existing DFT package S/PHI/nX allows us toachieve an ef?cient and ?exible code, by employing the existing, highly optimised minimisation routines with only minor modi?cations. We have used our software for a parisonof k 一個對稱的(111)導(dǎo)向的InxGa1xAs量子點更詳細(xì)的討論將在別處出版(Marquardt等人)。我們發(fā)現(xiàn)前兩個激發(fā)的空狀態(tài)被退化了,由于正在審議的C3v對稱系統(tǒng)。meV(砷化鎵傳導(dǎo)帶:Ecb(砷化鎵)=892meV)。我們的模擬受益只有一個本地化的電子狀態(tài)與固體能量我們的模型量子點有一個基本的長度80一個這樣詳細(xì)描述的形式體系將在其他地方發(fā)表(Marquardt等),相應(yīng)的旋轉(zhuǎn)連續(xù)彈性模型可以被發(fā)現(xiàn)在Schulz等人2011年。因此,我們已經(jīng)分析的旋轉(zhuǎn)8頻段K這個問題可以通過借用一個適合沿[111]軸生長的量子點描述的哈密頓克服,這個過程使得沿生長軸描述模擬細(xì)胞比沿平面方向更準(zhǔn)確。 站點控制的在(111)表面上生長的砷化銦鎵/砷化鎵量子點 就像在介紹中討論的,一個逼真的電子特性的描訴,Pelucchi等(2007年)和朱等(2007年)點控制的InxGa1XAs量子點是非常昂貴的計算使用一個標(biāo)準(zhǔn)的8頻段K 圖2 四孔狀態(tài)最接近的頻帶間隙和結(jié)合的能量在(111)(111)視圖。 圖1 InAs的頻帶結(jié)構(gòu)從近似的不同水平的KP模型得到重現(xiàn)(左)。由此可以得出的結(jié)論是一個14波段K這個分裂在這些狀態(tài)E(_e2 )–E(_e1)之間顯示為QD基礎(chǔ)長度的功能圖1(右)。MeV的范圍。我們唯一感興趣的是關(guān)于大容量的電子結(jié)構(gòu)哈密頓的正確的對稱描述,應(yīng)變和壓電的潛能已經(jīng)被忽視了,牢記后者的貢獻(xiàn)將獨立系統(tǒng)的對稱性減少到C2v對稱性正確的描述在8頻段或EMA圖片。nm,在以往的研究范圍(Stier 2000年。像這樣的一個分裂不會發(fā)生在任何其他模型中,這表明了BIA在14波段的情況下正確的描述(細(xì)虛線紅線)。CBVB耦合通過凱恩參數(shù)EP考慮到在八帶模型(藍(lán)色虛線)中顯著修改。InAs的頻帶結(jié)構(gòu)可以從不同的模型重現(xiàn)如圖1(左)。 P哈密頓從Bahder(1990年)(八頻帶模型)和Pfeffer和Zawadzki(1996)(14頻帶模型)用從Schliwa等(2007年)和Jancu等(2005年)得到的參數(shù)。隨后,我們研究過plike電子態(tài)的能級分裂在一個金字塔形的砷化銦/砷化鎵量子點用這些模型。P模型能夠重現(xiàn)正確的BIA在ZB晶格中,即使在一個連續(xù)的圖片中。正如Jancu等(2005年),Hermann和Weisbch(1977年)所訴,一個14波段K 夸特等2008)。像(截斷)錐體或晶格狀量子點的結(jié)構(gòu),這增加了人工C4v的對稱性。然而我們已經(jīng)看到了一個優(yōu)秀的定量協(xié)議的電子和空洞固有能量,此外我們可以觀察一個小的分裂在第一個兩個興奮,Plike電子狀態(tài)在ETBM,沒有受雇的K?P模型能夠重現(xiàn),類似以前的模擬在InAs量子點(貝斯特和Zunger2005)。 p model, we have calculated the electronic properties ofrealistic InxGa1?xAs QDs grown along the [111]direction. Our model QD has a base lengthof 80 nm and a height of nm, with an In content of x = , following experimentalevidence (Mereni et al. 2009). Our simulations yield only a single localised electron statewith the eigenenergy E(0e) = meV (GaAs conduction band: Ecb (GaAs) = 892 meV).The stronger localised hole ground and ?rst three excited states are shown in Fig. 2, togetherwith their corresponding eigenenergies (GaAs valence band: Evb(GaAs) = ?627 meV). We?nd the ?rst two excited hole states to be degenerate, due to the C3vsymmetry of the systemunder consideration. In the above analysis, strain and piezoelectric potentials were neglected.A more detailed discussion of symmetry properties of (111)oriented Inx Ga1?xAs QDs willbe published elsewhere (Marquardt et al.).3 模型的應(yīng)用 大多數(shù)倒置的各項異性多波段K?P模型 我們以前已經(jīng)比較了原子論的經(jīng)驗以緊密結(jié)合的方法(ETBM)和連續(xù)k?P方法為了電子性質(zhì)的描述在立方氮化鎵/氮化鋁量子點(馬夸特等2008)。 p model (Healy et al. 2009). This problemcan be overe by employing a Hamiltonian that is suited for the description of QDs grownalong the [111]axis, as this procedure allows to discretise the simulation cell along the growthaxis more accurately than along the inplane directions. As the symmetry of the binedsystem of crystal structure and triangular QD shape is C3vsymmetric (Baer et al. 2007),an ei