Reversing the Weak Quantum Measurement for a Photonic Qubit

We demonstrate the conditional reversal of a weak (partial-collapse) quantum measurement on a photonic qubit. The weak quantum measurement causes a nonunitary transformation of a qubit which is subsequently reversed to the original state after a successful reversing operation. Both the weak measurement and the reversal operation are implemented linear optically. The state recovery fidelity, determined by quantum process tomography, is shown to be over 94% for partial-collapse strength up to 0.9. We also experimentally study information gain due to the weak measurement and discuss the role of the reversing operation as an information erasure

The dream of the butterfly: experimental illusions in motion graphics

The Dream of the Butterfly: Experimental Illusions in Motion Graphics is a series of motion graphics and applications defined from visual illusions, which are based on the study of patterns and interactive multimedia. This project is not only focused on making and showing motion graphic pieces, but also providing a basis of studies and enough of the experimental process of creating them, by incorporating sections for the user to interact with. By creating a web-based interface, it provides people with a chance to experiment with the elements of basic patterns and understand visual illusions which were chosen by me for my thesis

Experimental verification of the commutation relation for Pauli spin operators using single-photon quantum interference

We report experimental verification of the commutation relation for Pauli spin operators using quantum interference of the single-photon polarization state. By superposing the quantum operations $\sigma_z \sigma_x$ and $\sigma_x \sigma_z$ on a single-photon polarization state, we have experimentally implemented the commutator, $[\sigma_{z}, \sigma_{x}]$, and the anticommutator, $\{\sigma_{z}, \sigma_{x}\}$, and have demonstrated the relative phase factor of $\pi$ between $\sigma_z \sigma_x$ and $\sigma_x \sigma_z$ operations. The experimental quantum operation corresponding to the commutator, $[\sigma_{z}, \sigma_{x}]=k\sigma_y$, showed process fidelity of 0.94 compared to the ideal $\sigma_y$ operation and $|k|$ is determined to be $2.12\pm0.18$.Comment: 4pages, 3 figure

Realizing Physical Approximation of the Partial Transpose

The partial transpose by which a subsystem's quantum state is solely transposed is of unique importance in quantum information processing from both fundamental and practical point of view. In this work, we present a practical scheme to realize a physical approximation to the partial transpose using local measurements on individual quantum systems and classical communication. We then report its linear optical realization and show that the scheme works with no dependence on local basis of given quantum states. A proof-of-principle demonstration of entanglement detection using the physical approximation of the partial transpose is also reported.Comment: 5 pages with appendix, 3 figure

Semantic radical knowledge and word recognition in Chinese for Chinese as foreign language learners

In the present study, we examined the relation of knowledge of semantic radicals to students’ language proficiency and word reading for adult Chinese-as-a-foreign language students. Ninety-seven college students rated their proficiency in speaking, listening, reading, and writing in Chinese, and were administered measures of receptive and productive knowledge of semantic radical position and function. A latent variable for language proficiency was constructed based on the number of semesters in Chinese courses, and students’ self-rating in Chinese. Two language proficiency groups were reliably formed. Students with higher language proficiency had significantly better performances on all the measures of knowledge of semantic radicals and word recognition. Furthermore, the receptive and productive knowledge of semantic radical position and productive knowledge of semantic radical function were positively related to word reading after controlling for proficiency level. Productive knowledge of semantic radical function was uniquely and positively related to word reading after accounting for proficiency level and other measures of semantic radical knowledge