Near-field memory

Near-field optics is another promising way to achieve high-density optical memory. Since near-field techniques overcome the diffraction limit of light by the contribution of evanescent wave, it is possible to store a bit datum in a nanometric region. The nanometric resolution is achieved by the contribution of evanescent fields. 

Naruse, M., Yatsui, T., Nomura, W., Hirose, N., Ohtsu, M. (2005). Hierarchy in optical near-fields and its application to memory retrieval. Optics Express, Vol. 13, pp. 9265-9271, 2005... 

Evanescent fields decay rapidly in the distance of sub-microns from some localized surface and cannot be usually observed, but they are enhanced by excitation of SPs and strongly depend upon nanometric structure of ultrathin films. Recently, evanescent fields are of great interest to evaluate nanometric spatial characteristics of ultrathin films and to fabricate ultrahigh-density optical memory, nano-devices, and so on [7]-[9]. And many types of scanning near-field optics microscope (SNOM) utilizing evanescent fields have been developed [10)-[12]. 

Aiming to address the demand for wireless sensors, the first ultra-low-power radiofrequency identification (RFID) wireless sensor tag with potentiometric input for use with pH and ion-selective electrodes was developed [181]. The proposed tag is able to autonomously measure and store electrode potential in its internal memory, and then transfer logged data wirelessly by RFID to a nearby reader or by near-field communication (NFC) to a smart phone. 

Each metal orbital type (t2g or eg) is spread out into a band, but the memory of the near-octahedral local crystal field is very clear. 

To make the matters worse, chemical reactions steepen scalar gradients and often, larger values of k ax need to be used. Since (kmax x max x k ax) values must be stored in the computer memory for each field for each time step, application of DNS to reactive flow processes is limited to moderate Reynolds numbers and Schmidt numbers near unity. The Damkohler number (ratio of charaeteristic time scales of small-scale mixing and chemical reaction, see Chapter 2) is generally limited to values less than 30 to 50. Even if huge computational resources are available, the DNS approach is difficult to apply to the realistic geometry of industrial chemical reactors. 

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