Slowing and stopping light using an optomechanical crystal array (1006.3829v2)

Abstract: One of the major advances needed to realize all-optical information processing of light is the ability to delay or coherently store and retrieve optical information in a rapidly tunable manner. In the classical domain, this optical buffering is expected to be a key ingredient to managing the flow of information over complex optical networks. Such a system also has profound implications for quantum information processing, serving as a long-term memory that can store the full quantum information contained in an optical pulse. Here we suggest a novel approach to light storage involving an optical waveguide coupled to an optomechanical crystal array, where light in the waveguide can be dynamically and coherently transferred into long-lived mechanical vibrations of the array. Under realistic conditions, this system is capable of achieving large bandwidths and storage/delay times in a compact, on-chip platform.

• The paper presents a novel method that transfers light from an optical waveguide into long-lived mechanical vibrations using an optomechanical crystal array.
• It employs integrated two-dimensional photonic crystal cavities on a silicon chip to achieve storage times in the microsecond range with gigahertz bandwidth.
• The work paves the way for scalable on-chip optical buffering and quantum memory applications through coherent photon-to-phonon conversion.

Analysis of Slowing and Stopping Light Using an Optomechanical Crystal Array

The paper "Slowing and stopping light using an optomechanical crystal array," authored by D.E. Chang et al., presents a novel approach to optical information processing by utilizing an optomechanical crystal array. The core advancement proposed involves the dynamic and coherent transfer of light from an optical waveguide into long-lived mechanical vibrations within an optomechanical crystal array. This approach is significant for both classical and quantum domains, aiming to achieve optical buffering and storage, respectively.

Summary of the Approach

The research presents an innovative methodology for storing and stopping light, which fundamentally relies on the interaction between an optical waveguide and an array of optomechanical crystals. The optomechanical system is composed of periodic structures that function as both photonic and phononic crystals, enabling the coherent conversion of optical information into mechanical energy. A key feature of this system is its ability to incorporate two-dimensional photonic crystal cavities in a planar setting, significantly maturing from previous iterations that facilitated nanoscale optical circuits. This integration on a silicon chip showcases significant potential for scalable on-chip photonic developments.

The paper's proposal involves resonant optical cavities in the optomechanical setup being driven optomechanically via a secondary cavity, where mechanical vibrations are inherently coupled to optical fields. The engineered system is leveraged to ensure complete destructiveness in wave reflections through specific optical and mechanical resonance alignments, enabling slowing and storage of optical pulses.

Key Results and Claims

The paper explores both theoretical and practical implications of photonic and mechanical interactions, emphasizing performance metrics such as bandwidth, delay/storage times, and scalability. One notable claim is the ability of this optomechanical configuration to maintain large operation bandwidths, on a chip-integrated platform, with substantial and long storage capabilities relative to conventional technologies.

In numerical terms, the authors address the potential to achieve storage times on the order of microseconds, which significantly surpasses the nanosecond storage limitations of purely optical systems. However, unlike atomic media counterparts, this system could feasibly manage gigahertz-range bandwidth due to its photonic crystal capabilities.

Theoretical and Practical Implications

From a theoretical standpoint, this research contributes to the formulation of optomechanical systems as a quantum interface, enhancing understanding of photon-to-phonon conversions. It marks another stepping stone towards integrating quantum information processing technologies in solid-state devices, potentially paving the way toward efficient quantum memories.

Practically, the system's on-chip scalability, with its potential for high integration densities, positions it as a compelling candidate for next-generation optical communication networks. It bypasses traditional electric signal conversion requirements, promoting all-optical data management that leverages mechanical degrees of freedom for enhanced functionality.

Future Speculations

The trajectory for future developments in this field appears robust. Enhancing the optomechanical interaction efficiencies and addressing mechanical noise limitations at cryogenic temperatures could elevate the application of this technology within quantum computing frameworks. Investigating further into coherent mechanical coupling and exploring alternative materials could open new avenues for optimizing and employing optomechanical systems in general-purpose computing technologies.

In conclusion, the paper introduces a forward-thinking approach to light manipulation within photonic structures, leveraging mechanical oscillations. The implications stretch across classical and quantum domains, with the potential to influence a broad spectrum of optical and computational technologies. The successful development and deployment of such systems could constitute a significant advancement in optical information processing on the microchip scale.