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nnm:faq [2022/01/18 15:25] carola.burkl [Can I take advantage of parallelization of the nextnano software on multi-core CPUs?] |
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- | ====== Frequently asked questions ====== | ||
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- | New documentation for FAQ https://www.nextnano.com/manual/faq/index.html | ||
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- | ==== I don't understand the $\bf{k} \cdot \bf{p}$ parameters ==== | ||
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- | In the literature, there are two different notations used: | ||
- | * Dresselhaus--Kip--Kittel (DKK): $L$, $M$, $N^+$, $N^-$ (zinc blende); $L_1$, $L_2$, $M_1$, $M_2$, $M_3$, $N_1^+$, $N_1^-$, $N_2^+$, $N_2^-$ (wurtzite) | ||
- | * Luttinger parameters: $\gamma_1$, $\gamma_2$, $\gamma_3$, $\kappa$ (zinc blende); Rashba--Sheka--Pikus (RSP) parameters $A_1$, $A_2$, $A_3$, $A_4$, $A_5$, $A_6$, $A_7$ (wurtzite) | ||
- | They are equivalent and can be converted into each other. | ||
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- | Some authors only use 3 parameters $L$, $M$, $N$ (or $\gamma_1$, $\gamma_2$, $\gamma_3$) which is fine for bulk semiconductors without magnetic field but not for heterostructures because the latter require 4 parameters, i.e. $N^+$, $N^-$ (instead of $N$ only) or $\kappa$. If these parameters are not known, they can be approximated. | ||
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- | There are different $\bf{k} \cdot \bf{p}$ parameters for | ||
- | * 6-band $\bf{k} \cdot \bf{p}$ and | ||
- | * 8-band $\bf{k} \cdot \bf{p}$. | ||
- | The 8-band $\bf{k} \cdot \bf{p}$ parameters can be calculated from the 6-band parameters taking into account the temperature dependent band gap $E_{\rm gap}$ and the Kane parameter $E_{\rm P}$ (zinc blende). For wurtzite the parameters are $E_{\rm gap}$ and the Kane parameters $E_{{\rm P}1}$, $E_{{\rm P}2}$. | ||
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- | The 8-band Hamiltonian also needs the conduction band mass parameter $S$ (zinc blende) or $S_1$, $S_2$ (wurtzite). | ||
- | They can be calculated from the conduction band effective mass $m_{\rm c}$, the band gap $E_{\rm gap}$, the spin-orbit split-off energy $\Delta_{\rm so}$ and the Kane parameter $E_{\rm P}$ (zinc blende). | ||
- | For wurtzite the parameters are $m_{{\rm c},\parallel}$, $m_{{\rm c},\perp}$, $E_{\rm gap}$, $\Delta_{\rm so}$, the crystal-field split-off energy $\Delta_{\rm cr}$ and the Kane parameters $E_{{\rm P}1}$, $E_{{\rm P}2}$. | ||
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- | Finally there is the inversion asymmetry parameter $B$ for zinc blende. For wurtzite there are $B_1$, $B_2$, $B_3$. | ||
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- | For more details on these equations, please refer to Section //3.1 The multi-band $\bf{k} \cdot \bf{p}$ Schrödinger equation// in the [[http://www.nextnano.com/downloads/publications/PhD_thesis_Stefan_Birner_TUM_2011_WSIBook.pdf|PhD thesis of S. Birner]]. | ||
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- | === Spurious solutions === | ||
- | Some people rescale the 8-band $\bf{k} \cdot \bf{p}$ in order to avoid //spurious solutions//. | ||
- | The 8-band $\bf{k} \cdot \bf{p}$ parameters can be calculated from the 6-band parameters taking into account the band gap $E_{\rm gap}$, the spin-orbit split-off energy $\Delta_{\rm so}$ and the Kane parameter $E_{\rm P}$ (zinc blende). For wurtzite the parameters are $E_{\rm gap}$, the spin-orbit split-off energy $\Delta_{\rm so}$, the crystal-field split-off energy $\Delta_{\rm cr}$ and the Kane parameters $E_{{\rm P}1}$, $E_{{\rm P}2}$. | ||
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- | For more details, please refer to Section //3.2 Spurious solutions// in the [[http://www.nextnano.com/downloads/publications/PhD_thesis_Stefan_Birner_TUM_2011_WSIBook.pdf|PhD thesis of S. Birner]]. | ||
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- | === Specific implementation nextnano++ === | ||
- | See section ''kp_8band{}'' in [[http://www.nextnano.com/nextnanoplus/software_documentation/input_file/quantum.htm|quantum{}]]. | ||
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- | === Specific implementation nextnano³ === | ||
- | * See section //Choice of $\bf{k} \cdot \bf{p}$ parameters// in [[http://www.nextnano.com/nextnano3/input_parser/keywords/numeric-control.htm|$numeric-control]]. | ||
- | * See section //$\bf{k} \cdot \bf{p}$ parameters// in [[http://www.nextnano.com/nextnano3/input_parser/database/docu/How-to-add-material-parameters.htm|Which material parameters are used?]]. | ||
- | * See section //Luttinger-parameters// in [[http://www.nextnano.com/nextnano3/input_parser/keywords/binary-zb-default.htm|$binary-zb-default]]. | ||
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- | ==== How shall I cite the nextnano software in publications? ==== | ||
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- | You can cite any of the following papers: | ||
- | * [[http://dx.doi.org/10.1109/TED.2007.902871|nextnano: General Purpose 3-D Simulations]]\\ S. Birner, T. Zibold, T. Andlauer, T. Kubis, M. Sabathil, A. Trellakis, P. Vogl \\ IEEE Trans. Electron Dev. **54**, 2137 (2007) | ||
- | * [[http://dx.doi.org/10.1007/s10825-006-0005-x|The 3D nanometer device project nextnano: Concepts, methods, results]]\\ A. Trellakis, T. Zibold, T. Andlauer, S. Birner, R. K. Smith, R. Morschl, P. Vogl\\ J. Comput. Electron. **5**, 285 (2006) | ||
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- | For simulations including electrolytes, you should cite: | ||
- | * [[http://stacks.iop.org/1742-6596/107/i=1/a=012002|Theoretical model for the detection of charged proteins with a silicon-on-insulator sensor]]\\ S. Birner, C. Uhl, M. Bayer, P. Vogl\\ J. Phys.: Conf. Ser. **107**, 012002 (2008) | ||
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- | For simulations that use the Contact Block Reduction method (CBR) (ballistic transport), you should cite any of the following papers: | ||
- | * [[http://dx.doi.org/10.1063/1.1560567|Efficient method for the calculation of ballistic quantum transport]]\\ D. Mamaluy, M. Sabathil, P. Vogl\\ J. Appl. Phys. **93**, 4628 (2003) | ||
- | * [[http://dx.doi.org/10.1007/s10825-009-0293-z|Ballistic quantum transport using the contact block reduction (CBR) method - An introduction]]\\ S. Birner, C. Schindler, P. Greck, M. Sabathil, P. Vogl\\ J. Comput. Electron. **8**, 267 (2009) | ||
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- | nextnano.MSB software: For simulations that use the multi-scattering Büttiker (MSB) probe model (NEGF), you should cite: | ||
- | * [[https://doi.org/10.1364/OE.23.006587|Efficient method for the calculation of dissipative quantum transport in quantum cascade lasers]]\\ P. Greck, S. Birner, B. Huber, P. Vogl\\ Optics Express **23**, 6587 | ||
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- | nextnano.QCLsoftware: For simulations that use the NEGF method, you should cite: | ||
- | * [[http://dx.doi.org/10.1103/PhysRevB.92.241306|Contrasting influence of charged impurities on transport and gain in terahertz quantum cascade lasers]]\\ T. Grange\\ Phys. Rev. B **92**, 241306(R) (2015) | ||
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- | For simulations that use the NEGF algorithm included in the nextnano³ software, you should cite any of these publications: | ||
- | * [[http://dx.doi.org/10.1063/1.4863665|Modeling techniques for quantum cascade lasers | ||
- | ]]\\ C. Jirauschek, T. Kubis\\ Appl. Phys. Rev. **1**, 011307 (2014) | ||
- | * [[https://doi.org/10.1103/PhysRevB.79.195323|Theory of non-equilibrium quantum transport and energy dissipation in terahertz quantum cascade lasers]]\\ T. Kubis, C. Yeh, P. Vogl, A. Benz, G. Fasching, C. Deutsch\\ Phys. Rev. B **79**, 195323 (2009) | ||
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- | There might be further papers in the literature that are more suited to be cited in certain cases. | ||
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