{ "cells": [ { "cell_type": "code", "execution_count": null, "id": "4f66c596-dc32-4b03-bf34-726a206eaff5", "metadata": {}, "outputs": [], "source": [ "# GUAN软件包官网: https://py.guanjihuan.com\n", "import guan\n", "guan.test()" ] }, { "cell_type": "code", "execution_count": null, "id": "214d56d6-1626-4fce-bc7d-9084c74cf4fc", "metadata": {}, "outputs": [], "source": [ "# 泡利矩阵\n", "import guan\n", "sigma_x = guan.sigma_x()\n", "print(sigma_x)" ] }, { "cell_type": "code", "execution_count": null, "id": "f8727100-fab6-487c-9d50-a9390aabe623", "metadata": {}, "outputs": [], "source": [ "# 函数的计时器\n", "import guan\n", "\n", "@guan.timer_decorator\n", "def my_function():\n", " import time\n", " time.sleep(2)\n", " print('Run finished!')\n", "\n", "for _ in range(3):\n", " my_function()" ] }, { "cell_type": "code", "execution_count": null, "id": "2778f460-f8c9-496e-a003-59394379bb20", "metadata": {}, "outputs": [], "source": [ "# 实空间哈密顿量的示例\n", "import guan\n", "print('\\n', guan.hamiltonian_of_finite_size_system_along_one_direction(3), '\\n')\n", "print(guan.hamiltonian_of_finite_size_system_along_two_directions_for_square_lattice(2, 2), '\\n')\n", "print(guan.hamiltonian_of_finite_size_system_along_three_directions_for_cubic_lattice(2, 2, 2), '\\n')" ] }, { "cell_type": "code", "execution_count": null, "id": "a08fb5f1-724c-43b1-ad4a-daa94b9f1605", "metadata": {}, "outputs": [], "source": [ "# 能带图计算示例\n", "import guan\n", "import numpy as np\n", "k_array = np.linspace(-np.pi, np.pi, 100)\n", " # one dimensional chain\n", "hamiltonian_function = guan.one_dimensional_fourier_transform_with_k(unit_cell=0, hopping=1)\n", "eigenvalue_array = guan.calculate_eigenvalue_with_one_parameter(k_array, hamiltonian_function)\n", "guan.plot(k_array, eigenvalue_array, xlabel='k', ylabel='E', style='-k', fontfamily=None)\n", "# square lattice ribbon\n", "eigenvalue_array = guan.calculate_eigenvalue_with_one_parameter(k_array, guan.hamiltonian_of_square_lattice_in_quasi_one_dimension)\n", "guan.plot(k_array, eigenvalue_array, xlabel='k', ylabel='E', style='-k', fontfamily=None)\n", "# graphene ribbon\n", "eigenvalue_array = guan.calculate_eigenvalue_with_one_parameter(k_array, guan.hamiltonian_of_graphene_with_zigzag_in_quasi_one_dimension)\n", "guan.plot(k_array, eigenvalue_array, xlabel='k', ylabel='E', style='-k', fontfamily=None)" ] }, { "cell_type": "code", "execution_count": null, "id": "adc6a47a-8b4f-416f-8bca-65ee2b068fb9", "metadata": {}, "outputs": [], "source": [ "# 陈数和Wilson loop计算示例\n", "import guan\n", "import numpy as np\n", "chern_number = guan.calculate_chern_number_for_square_lattice_with_efficient_method(guan.hamiltonian_of_one_QAH_model, precision=100)\n", "print('\\nChern number=', chern_number, '\\n')\n", "wilson_loop_array = guan.calculate_wilson_loop(guan.hamiltonian_of_ssh_model)\n", "print('Wilson loop =', wilson_loop_array)\n", "p = np.log(wilson_loop_array)/2/np.pi/1j\n", "print('\\np =', p, '\\n')" ] }, { "cell_type": "code", "execution_count": null, "id": "44aa1ca5-ca8b-4afc-a719-d40736edeee5", "metadata": {}, "outputs": [], "source": [ "# 使用格林函数计算态密度示例\n", "import guan\n", "import numpy as np\n", "\n", "hamiltonian = guan.hamiltonian_of_finite_size_system_along_two_directions_for_square_lattice(2,2)\n", "fermi_energy_array = np.linspace(-4, 4, 400)\n", "total_dos_array = guan.total_density_of_states_with_fermi_energy_array(fermi_energy_array, hamiltonian, broadening=0.1)\n", "guan.plot(fermi_energy_array, total_dos_array, xlabel='E', ylabel='Total DOS', style='-', fontfamily=None)\n", "\n", "fermi_energy = 0\n", "N1 = 3\n", "N2 = 4\n", "hamiltonian = guan.hamiltonian_of_finite_size_system_along_two_directions_for_square_lattice(N1,N2)\n", "LDOS = guan.local_density_of_states_for_square_lattice(fermi_energy, hamiltonian, N1=N1, N2=N2)\n", "print('square lattice:\\n', LDOS, '\\n')\n", "h00 = guan.hamiltonian_of_finite_size_system_along_one_direction(N2)\n", "h01 = np.identity(N2)\n", "LDOS = guan.local_density_of_states_for_square_lattice_using_dyson_equation(fermi_energy, h00=h00, h01=h01, N2=N2, N1=N1)\n", "print(LDOS, '\\n\\n')\n", "LDOS2 = guan.local_density_of_states_for_square_lattice_using_dyson_equation_with_second_method(fermi_energy, h00, h01, N2, N1, internal_degree=1, broadening=0.01)\n", "print(LDOS2, '\\n\\n')\n", "guan.plot_contour(range(N1), range(N2), LDOS, fontfamily=None)\n", "guan.plot_contour(range(N1), range(N2), LDOS2, fontfamily=None)\n", "\n", "N1 = 3\n", "N2 = 4\n", "N3 = 5\n", "hamiltonian = guan.hamiltonian_of_finite_size_system_along_three_directions_for_cubic_lattice(N1, N2, N3)\n", "LDOS = guan.local_density_of_states_for_cubic_lattice(fermi_energy, hamiltonian, N1=N1, N2=N2, N3=N3)\n", "print('cubic lattice:\\n', LDOS, '\\n')\n", "h00 = guan.hamiltonian_of_finite_size_system_along_two_directions_for_square_lattice(N2, N3)\n", "h01 = np.identity(N2*N3)\n", "LDOS = guan.local_density_of_states_for_cubic_lattice_using_dyson_equation(fermi_energy, h00, h01, N3=N3, N2=N2, N1=N1)\n", "print(LDOS)" ] }, { "cell_type": "code", "execution_count": null, "id": "cdfd4123-dcb2-4dc5-9e48-a35728fd7168", "metadata": {}, "outputs": [], "source": [ "# 电导和散射矩阵的计算示例\n", "import guan\n", "import numpy as np\n", "\n", "fermi_energy_array = np.linspace(-4, 4, 400)\n", "h00 = guan.hamiltonian_of_finite_size_system_along_one_direction(4)\n", "h01 = np.identity(4)\n", "conductance_array = guan.calculate_conductance_with_fermi_energy_array(fermi_energy_array, h00, h01)\n", "guan.plot(fermi_energy_array, conductance_array, xlabel='E', ylabel='Conductance', style='-', fontfamily=None)\n", "\n", "fermi_energy = 0\n", "guan.print_or_write_scattering_matrix(fermi_energy, h00, h01)" ] }, { "cell_type": "code", "execution_count": null, "id": "fd0f2bcc-82cd-4951-8b4b-e6913d767008", "metadata": {}, "outputs": [], "source": [ "# 波函数规范的选取示例\n", "import numpy as np\n", "import cmath\n", "import guan\n", "\n", "# Fixed gauge example 1\n", "vector = np.array([np.sqrt(0.5), np.sqrt(0.5)])*cmath.exp(np.random.uniform(0, 1)*1j)\n", "print('\\nExample 1\\n', vector)\n", "print(np.dot(vector.transpose().conj(), vector), '\\n')\n", "\n", "vector = guan.find_vector_with_fixed_gauge_by_making_one_component_real(vector)\n", "print(vector)\n", "print(np.dot(vector.transpose().conj(), vector), '\\n')\n", "\n", "# Fixed gauge example 2\n", "vector = np.array([1, 0])*cmath.exp(np.random.uniform(0, 1)*1j)\n", "print('\\nExample 2\\n', vector)\n", "print(np.dot(vector.transpose().conj(), vector), '\\n')\n", "\n", "vector = guan.find_vector_with_fixed_gauge_by_making_one_component_real(vector)\n", "print(vector)\n", "print(np.dot(vector.transpose().conj(), vector), '\\n')" ] }, { "cell_type": "code", "execution_count": null, "id": "444c5848-c50d-4fb3-b71c-056b5005620b", "metadata": {}, "outputs": [], "source": [ "# 数组分割示例\n", "import numpy as np\n", "import guan\n", "cpus = 4\n", "parameter_array_all = np.arange(0, 17, 1) \n", "for task_index in range(cpus):\n", " parameter_array = guan.preprocess_for_parallel_calculations(parameter_array_all, cpus, task_index)\n", " print(parameter_array)\n", " print()" ] } ], "metadata": { "kernelspec": { "display_name": "Python 3 (ipykernel)", "language": "python", "name": "python3" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 3 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython3", "version": "3.11.7" } }, "nbformat": 4, "nbformat_minor": 5 }