Long-term large-scale holographic storage in iron doped lithium niobate

The centerpiece of my work described in this thesis is a large-scale fast random-access holographic memory using LiNbO{dollar}sb3{dollar}:Fe. This system is described in detail in Chapter 2 and 3 and has been used repeatedly and extensively through all of our works. In Chapter 2, various design issues related to this system are discussed. High, system dynamic-range-limited storage capacity is demonstrated by using angle, fractal and spatial multiplexing with a key custom-designed component--the segmented mirror array. The SNR and BER obtained from the reconstructed information are comparable to those of conventional CD-ROMs.; Fast random access to the memory contents is materialized in a separate system using an acousto-optic deflector (AOD) as the addressing device and an electro-optic modulator (EOM) to compensate for the Doppler shift. Chapter 3 discusses the design issues and presents experimental demonstration of holographic storage using the system. The design and application of an optical phase-lock loop using the AOD and EOM for phase stabilization are also described at the end of this chapter.; Chapter 4 and 5 address two methods of thermal fixing to solve the volatility problem in holographic memories using photorefractive materials. First, "Low-High-Low" fixing is described in Chapter 4, along with the characterization of system error performance of non-volatile holographic storage using thermal fixing. A novel "incremental fixing schedule" is introduced to improve the system fixing efficiency. Experimental demonstration of a large-scale non-volatile memory with good error performance is also presented.; Chapter 5 shows theoretical treatment and experimental demonstration of high-temperature recording in LiNbO{dollar}sb3{dollar}:Fe. Different charge transport mechanisms and their influence on the dynamics of holographic recording as well as the system dynamic range are discussed in detail. The two thermal fixing methods are examined and compared in terms of the M/#.; In Chapter 6, a very important holographic noise source, the inter-pixel grating noise, is evaluated theoretically based on a linear (small-signal) model, followed by experimental investigation of its influence on the system error performance of a large-scale memory. Random-phase modulation in the signal beam is discussed and demonstrated as an effective way to suppress this holographic noise.