Related papers: Single-ion phonon laser in the quantum regime
We show that the physical system consisting of trapped ions interacting with lasers may undergo a rich variety of quantum phase transitions. By changing the laser intensities and polarizations the dynamics of the internal states of the ions…
Quantum cascade lasers are unipolar semiconductor lasers covering a wide range of the infrared and terahertz spectrum. Lasing action is achieved by using optical intersubband transitions between quantized states in specifically designed…
We present a protocol that permits the generation of a subtle with superposition with 2^(l+1) displaced number states on a circle in phase space as target state for the center-of-mass motion of a trapped ion. Through a sequence of 'l'…
We present a self-contained operator-based approach to derive the spectrum of trapped ions. This approach provides the complete normal form of the low energy quadratic Hamiltonian in terms of bosonic phonons, as well as an effective free…
We study the steady state motion of a single trapped ion oscillator driven to the nonlinear regime. Damping is achieved via Doppler laser-cooling. The ion motion is found to be well described by the Duffing oscillator model with an…
Measuring the phonon number of the laser-cooled ions is an indispensable step in evaluating whether an ion is in ground state. At present, commonly used methods in the experiments are red-to-blue sideband ratios and adiabatic evolution…
We present a universal algorithm for an efficient deterministic preparation of an arbitrary two--mode bosonic state. In particular, we discuss in detail preparation of entangled states of a two-dimensional vibrational motion of a trapped…
Detecting extremely small forces helps exploring new physics quantitatively. Here we demonstrate that the phonon laser made of a single trapped $^{40}$Ca$^{+}$ ion behaves as an exquisite sensor for small force measurement. We report our…
Extending quantum control to increasingly complex systems is crucial for both advancing quantum technologies and fundamental physics. In trapped ion systems, quantum logic techniques that combine a well-controlled logic species with a more…
We describe a simplified scheme for quantum logic with a collection of laser-cooled trapped atomic ions. Building on the scheme of Cirac and Zoller, we show how the fundamental controlled-NOT gate between a collective mode of ion motion and…
Entangled coherent states play pivotal roles in various fields such as quantum computation, quantum communication, and quantum sensing. We experimentally demonstrate the generation of entangled coherent states with the two-dimensional…
We propose a dissipative method for preparation of a maximally entangled steady state of two trapped ions in the Lamb-Dicke limit. By addressing the trapped-ion system with a monochromatic standing wave laser pulse of frequency resonant…
We study squeezed states of phonons, which allow a reduction in the quantum fluctuations of the atomic displacements to below the zero-point quantum noise level of coherent phonon states. We investigate the generation of squeezed phonon…
The generation of quantum entangled states of many particles is a central goal of quantum information science. Characterizing such states is a complex task that demands exponentially large resources as particles are being added. Previously,…
Quantum technologies, holding the promise of exponentially superior performance than their classical counterparts for certain tasks, have consistently encountered challenges, including instability in quantum light sources, quantum…
This work reports a fully guided setup for single-mode squeezing generation on integrated titanium-indiffused periodically poled nonlinear resonators. A continuous wave laser beam is delivered and the squeezed field is collected by…
Quantum state tomography is the experimental procedure of determining an unknown state. It is not only essential for the verification of resources and processors of quantum information but is also important in its own right with regard to…
We investigate, using the stochastic limit method, the coherent quantum control of a 3-level atom in $\Lambda$-configuration interacting with two laser fields. We prove that, in the generic situation, this interaction entangles the two…
Synthesis of the Einstein-Podolsky-Rosen entangled state --- the primary entangled resource in continuous-variable quantum-optical information processing --- is a technological challenge of great importance. Here we propose and implement a…
Quantum technologies are powered by platforms to generate complex non-classical states of matter or light to realize applications. We investigate the non-classical properties of high-harmonic generation in semiconductors, an emerging…