http://www.compadre.org/quantum/ The latest material additions to the Quantum Exchange. en-US Copyright 2008, ComPADRE.org managingEditor@compadre.org editor@thequantumexchange.org Thu, 12 Jun 2008 12:28:47 EST http://blogs.law.harvard.edu/tech/rss http://www.compadre.org/portal/services/images/LogoSmallQuantum.gif http://www.compadre.org/quantum/ 125 35 http://www.compadre.org/quantum/items/detail.cfm?ID=7353 This journal article argues that it is important to introduce quantum theory in college freshman physics classes. The author shows from experience how a teacher can teach the subject without using advanced mathematics and provides specific strategies, along with examples, on the most effective ways to introduce various quantum principles. These examples include the photoelectric effect, particle theory of radiation, wave-matter duality, the quantum atom, uncertainty principles, interconnectedness principle, and the Copenhagen interpretation. Quantum Physics/Quantum Experiments http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=7353 Thu, 12 Jun 2008 12:28:47 EST http://www.compadre.org/quantum/items/detail.cfm?ID=7353 http://www.compadre.org/quantum/items/detail.cfm?ID=7076 This animation shows the quantum analogy of a classical bouncing ball moving in a gravitational field, without dissipation. The video shows the wave packet motion next to the ball. A graph of the expectation value of the quantum ball versus time is provided that illustrates the dispersion and later reforming of the quantum wave packet. Quantum Physics/Scattering and Continuum State Systems http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=7076 Tue, 13 May 2008 17:34:22 EST http://www.compadre.org/quantum/items/detail.cfm?ID=7076 http://www.compadre.org/quantum/items/detail.cfm?ID=6954 Quantum mechanics is both a topic of great importance to modern science, engineering, and technology, and a topic with many inherent barriers to learning and understanding. Computational resources are vital tools for developing deep conceptual understanding of quantum systems for students new to the subject. This article outlines two projects that are taking an open source/open access approach to create and share teaching and learning resources for quantum physics. The Open Source Physics project provides program libraries, programming tools, example simulations, and pedagogical resources for instructors wishing to give a rich experience to their students. These simulations and student activities are, in turn, being integrated into a world?wide collection of teaching and learning resources available through the Quantum Exchange, a part of the ComPADRE Portal to the National Science Digital Library. Both of these projects use technologies that encourage community development and collaboration. Using these tools, faculty can create learning experiences, share and discuss their content with others, and combine resources in new ways. Examples of the available content and tools are given, along with an introduction to accessing and using these resources. Education Practices/Technology/Computers http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=6954 Mon, 28 Apr 2008 14:02:14 EST http://www.compadre.org/quantum/items/detail.cfm?ID=6954 http://www.compadre.org/quantum/items/detail.cfm?ID=6822 The QM Momentum Measurement program displays the time evolution of the position-space wave function and can be used to simulate the quantum-mechanical measurement of momentum to a finite precision. The default wave function is an equal-mix four-state superposition in the infinite square well. QM Momentum Measurement is one of 18 Open Source Physics programs that model time-dependent quantum mechanics using an energy eigenstate expansion. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the qm_measurement_p.jar file will run the program if Java is installed. Other programs provide additional visualizations. They can be found by searching ComPADRE for Open Source Physics, OSP, or Superposition. Quantum Physics/Foundations and Measurement Theory http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=6822 Thu, 17 Apr 2008 00:19:25 EST http://www.compadre.org/quantum/items/detail.cfm?ID=6822 http://www.compadre.org/quantum/items/detail.cfm?ID=6821 The QM Position Measurement program displays the time evolution of the position-space wave function and can be used to simulate the quantum-mechanical measurement of position to a finite precision. The default wave function is an equal-mix four-state superposition in the infinite square well. QM Position Measurement is one of 18 Open Source Physics programs that model time-dependent quantum mechanics using an energy eigenstate expansion. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the qm_measurement_x.jar file will run the program if Java is installed. Other programs provide additional visualizations. They can be found by searching ComPADRE for Open Source Physics, OSP, or Superposition. Quantum Physics/Foundations and Measurement Theory http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=6821 Thu, 17 Apr 2008 00:15:51 EST http://www.compadre.org/quantum/items/detail.cfm?ID=6821 http://www.compadre.org/quantum/items/detail.cfm?ID=6815 The QM Energy Measurement program displays the time evolution of the position-space wave function and can be used to simulate the quantum-mechanical measurement of energy. The default wave function is an equal-mix four-state superposition in the infinite square well. QM Energy Measurement is one of 18 Open Source Physics programs that model time-dependent quantum mechanics using an energy eigenstate expansion. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the qm_measurement_e.jar file will run the program if Java is installed. Other programs provide additional visualizations. They can be found by searching ComPADRE for Open Source Physics, OSP, or Superposition. Quantum Physics/Foundations and Measurement Theory http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=6815 Thu, 17 Apr 2008 00:12:17 EST http://www.compadre.org/quantum/items/detail.cfm?ID=6815 http://www.compadre.org/quantum/items/detail.cfm?ID=6813 The QM Wigner program displays the time evolution of the position-space wave function and the associated quasi-probability distribution in phase space via the Wigner function. The default wave function is a Gaussian wave packet in a harmonic oscillator. Additional states and other potential energy functions can be specified using the Display | Switch GUI menu item. QM Wigner is one of 18 Open Source Physics programs that model time-dependent quantum mechanics using an energy eigenstate expansion. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the qm_wigner.jar file will run the program if Java is installed. Other programs provide additional visualizations. They can be found by searching ComPADRE for Open Source Physics, OSP, or Superposition. Quantum Physics/Bound State Systems http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=6813 Wed, 16 Apr 2008 23:37:24 EST http://www.compadre.org/quantum/items/detail.cfm?ID=6813 http://www.compadre.org/quantum/items/detail.cfm?ID=6812 The QM Momentum Carpet program displays the time evolution of the position-space wave function and the associated quantum-mechanical momentum-time diagram, the momentum-space quantum carpet. The default wave function is a Gaussian wave packet in an infinite square well. Additional states and other potential energy functions can be specified using the Display | Switch GUI menu item. QM Momentum Carpet is one of 18 Open Source Physics programs that model time-dependent quantum mechanics using an energy eigenstate expansion. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the qm_momentun_carpet.jar file will run the program if Java is installed. Other programs provide additional visualizations. They can be found by searching ComPADRE for Open Source Physics, OSP, or Superposition. Quantum Physics/Bound State Systems http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=6812 Wed, 16 Apr 2008 23:16:15 EST http://www.compadre.org/quantum/items/detail.cfm?ID=6812 http://www.compadre.org/quantum/items/detail.cfm?ID=6810 The QM Carpet program displays the time evolution of the position-space wave function and the associated quantum-mechanical space-time diagram, the quantum carpet. The default wave function is a Gaussian wave packet in an infinite square well. Additional states and other potential energy functions can be specified using the Display | Switch GUI menu item. QM Carpet is one of 18 Open Source Physics programs that model time-dependent quantum mechanics using an energy eigenstate expansion. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the qm_carpet.jar file will run the program if Java is installed. Other programs provide additional visualizations. They can be found by searching ComPADRE for Open Source Physics, OSP, or Superposition. Quantum Physics/Bound State Systems http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=6810 Wed, 16 Apr 2008 23:09:27 EST http://www.compadre.org/quantum/items/detail.cfm?ID=6810 http://www.compadre.org/quantum/items/detail.cfm?ID=6811 The QM Momentum Space program displays the time evolution of the position-space wave function and the associated momentum-space wave function. The default wave function is a Gaussian wave packet in a harmonic oscillator. Additional states and other potential energy functions can be specified using the Display | Switch GUI menu item. QM Momentum Space is one of 18 Open Source Physics programs that model time-dependent quantum mechanics using an energy eigenstate expansion. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the qm_fft.jar file will run the program if Java is installed. Other programs provide additional visualizations. They can be found by searching ComPADRE for Open Source Physics, OSP, or Superposition. Quantum Physics/Bound State Systems http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=6811 Wed, 16 Apr 2008 22:43:28 EST http://www.compadre.org/quantum/items/detail.cfm?ID=6811 http://www.compadre.org/quantum/items/detail.cfm?ID=6809 The QM Momentum Expectation Value program displays the time evolution of the position-space wave function and the associated momentum expectation value. The default wave function is a Gaussian wave packet in a harmonic oscillator. Additional states and other potential energy functions can be specified using the Display | Switch GUI menu item. QM Momentum Expectation Value is one of 18 Open Source Physics programs that model time-dependent quantum mechanics using an energy eigenstate expansion. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the qm_expectation_p.jar file will run the program if Java is installed. Other programs provide additional visualizations. They can be found by searching ComPADRE for Open Source Physics, OSP, or Superposition. Quantum Physics/Bound State Systems http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=6809 Wed, 16 Apr 2008 22:17:52 EST http://www.compadre.org/quantum/items/detail.cfm?ID=6809 http://www.compadre.org/quantum/items/detail.cfm?ID=6807 The QM Position Expectation Value program displays the time evolution of the position-space wave function and the associated position expectation value. The default wave function is a two-state superposition of infinite square well states. Additional states and other potential energy functions can be specified using the Display | Switch GUI menu item. QM Position Expectation Value is one of 18 Open Source Physics programs that model time-dependent quantum mechanics using an energy eigenstate expansion. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the qm_expectation_x.jar file will run the program if Java is installed. Other programs provide additional visualizations. They can be found by searching ComPADRE for Open Source Physics, OSP, or Superposition. Quantum Physics/Bound State Systems http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=6807 Wed, 16 Apr 2008 21:49:48 EST http://www.compadre.org/quantum/items/detail.cfm?ID=6807 http://www.compadre.org/quantum/items/detail.cfm?ID=6799 The QM Probability program displays the time evolution of the position-space wave function and the associated probability density. The default wave function is the n = 5 state in a ramped infinite square well. Additional states and other potential energy functions can be specified using the Display | Switch GUI menu item. QM Probability is one of 18 Open Source Physics programs that model time-dependent quantum mechanics using an energy eigenstate expansion. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the qm_probability.jar file will run the program if Java is installed. Other programs provide additional visualizations. They can be found by searching ComPADRE for Open Source Physics, OSP, or Superposition. Quantum Physics/Probability, Waves, and Interference http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=6799 Wed, 16 Apr 2008 21:34:02 EST http://www.compadre.org/quantum/items/detail.cfm?ID=6799 http://www.compadre.org/quantum/items/detail.cfm?ID=6868 The QM Superposition program displays the time evolution of the position-space wave function. It is distributed as part of a zip file that contains the ready-to-run (compiled) code, as well as additional documentation, exercises, and data files. Unzip the distribution and double click the qm_superposition.jar file which will run the program if Java is installed. The default wave function shows a two-state superposition of harmonic oscillator states. Other configurations can be observed by loading data files using the File | Load XML menu item. QM Superposition is one of 18 Open Source Physics programs that model time-dependent quantum mechanics using an energy eigenstate expansion. Other programs provide additional visualizations. They can be found by searching ComPADRE for Open Source Physics, OSP, or Superposition. Quantum Physics/Bound State Systems http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=6868 Tue, 15 Apr 2008 15:33:40 EST http://www.compadre.org/quantum/items/detail.cfm?ID=6868 http://www.compadre.org/quantum/items/detail.cfm?ID=6814 The QM Measurement program displays the time evolution of the position-space wave function and can be used to simulate the quantum-mechanical measurements of energy, position, and/or momentum. The default wave function is an equal-mix four-state superposition in the infinite square well. Additional states and other potential energy functions can be specified using the Display | Switch GUI menu item. QM Measurement is one of 18 Open Source Physics programs that model time-dependent quantum mechanics using an energy eigenstate expansion. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the qm_measurement.jar file will run the program if Java is installed. Other programs provide additional visualizations. They can be found by searching ComPADRE for Open Source Physics, OSP, or Superposition. Quantum Physics/Foundations and Measurement Theory http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=6814 Thu, 10 Apr 2008 12:49:14 EST http://www.compadre.org/quantum/items/detail.cfm?ID=6814 http://www.compadre.org/quantum/items/detail.cfm?ID=6798 The QM Superposition program displays the time evolution of the position-space wave function. The default wave function shows a two-state superposition of harmonic oscillator states. Additional states and other potential energy functions can be specified using the Display | Switch GUI menu item. QM Superposition is one of 18 Open Source Physics programs that model time-dependent quantum mechanics using an energy eigenstate expansion. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the qm_superposition.jar file will run the program if Java is installed. Other programs provide additional visualizations. They can be found by searching ComPADRE for Open Source Physics, OSP, or Superposition. Quantum Physics/Bound State Systems http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=6798 Thu, 10 Apr 2008 12:21:17 EST http://www.compadre.org/quantum/items/detail.cfm?ID=6798 http://www.compadre.org/quantum/items/detail.cfm?ID=3364 This desktop application simulates quantum computation algorithms on a computer. The user may use or modify sample algorithms or create new ones. Tutorials and information about quantum computing algorithms are available. A demo version is available as a free download, with reduced functionality. Quantum Physics/Entanglement and Quantum Information http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=3364 Sat, 15 Mar 2008 10:32:58 EST http://www.compadre.org/quantum/items/detail.cfm?ID=3364 http://www.compadre.org/quantum/items/detail.cfm?ID=3361 This series of video lectures is designed to be used either as an introduction to the quantum theory of computation or as an introduction to quantum physics itself. The level of mathematics used is relatively low, requiring only that the viewer understand the concepts of eigenvalues and vector spaces. The lectures are accompanied by problem and solutions sets. Quantum Physics/Entanglement and Quantum Information http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=3361 Sat, 15 Mar 2008 10:07:07 EST http://www.compadre.org/quantum/items/detail.cfm?ID=3361 http://www.compadre.org/quantum/items/detail.cfm?ID=6475 This self-contained file contains Open Source Physics programs for the teaching of time evolution and visualization of quantum-mechanical bound states. The suite of programs is based on the ability to expand an arbitrary wave function in terms of basis vectors in a reduced Hilbert space (the superposition principle). One can choose from several real-time visualizations, such as the position and momentum expectation values and the Wigner quasi-probability distribution for position and momentum. We describe how these tools can be used to study the long-term time-dependent properties of quantum-mechanical systems. The materials and text of this resource appeared in an article of the same name in the Theme Double-Issue on Computation and Computer-based Instruction in the American Journal of Physics [Am. J. Phys. 76, No. 4&5, pp. 385-392 (2008)]. Quantum Physics/Bound State Systems http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=6475 Thu, 07 Feb 2008 12:24:05 EST http://www.compadre.org/quantum/items/detail.cfm?ID=6475 http://www.compadre.org/quantum/items/detail.cfm?ID=5170 This simulation illustrates the energy dispersion of electrons in a 2D hexagonal lattice. The density of states in energy is also graphed. This applet allows for selecting the Fermi energy of interest and the ratio of nearest neighbor overlap integrals. Modern Physics/Condensed Matter http://www.compadre.org/quantum/bulletinboard/Thread.cfm?ID=5170 Fri, 09 Nov 2007 06:57:40 EST http://www.compadre.org/quantum/items/detail.cfm?ID=5170