@article{GuoSekiMiyamotoetal.2014,
  author    = {Guo, Yuanyuan and Seki, Kosuke and Miyamoto, Ko-ichiro and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {Novel photoexcitation method for light-addressable potentiometric sensor with higher spatial resolution},
  series = {Applied physics express : APEX},
  volume    = {7},
  journal   = {Applied physics express : APEX},
  number    = {6},
  publisher = {IOP},
  address   = {Bristol},
  issn      = {1882-0786 (E-Journa); 1882-0778 (Print)},
  doi       = {10.7567/APEX.7.067301},
  pages     = {067301-4},
  year      = {2014},
  abstract  = {A novel photoexcitation method for the light-addressable potentiometric sensor (LAPS) is proposed to achieve a higher spatial resolution of chemical images. The proposed method employs a combined light source that consists of a modulated light probe, which generates the alternating photocurrent signal, and a ring of constant illumination surrounding it. The constant illumination generates a sheath of carriers with increased concentration which suppresses the spread of photocarriers by enhanced recombination. A device simulation was carried out to verify the effect of constant illumination on the spatial resolution, which demonstrated that a higher spatial resolution can be obtained.},
  language  = {en}
}
@article{GuoSekiMiyamotoetal.2014,
  author    = {Guo, Yuanyuan and Seki, Kosuke and Miyamoto, Ko-ichiro and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {Device simulation of the light-addressable potentiometric sensor with a novel photoexcitation method for a higher spatial resolution},
  series = {Procedia Engineering},
  volume    = {87},
  journal   = {Procedia Engineering},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1877-7058},
  doi       = {10.1016/j.proeng.2014.11.369},
  pages     = {456 -- 459},
  year      = {2014},
  abstract  = {A novel photoexcitation method for the light-addressable potentiometric sensor (LAPS) realized a higher spatial resolution of chemical imaging. In this method, a modulated light probe, which generates the alternating photocurrent signal, is surrounded by a ring of constant light, which suppresses the lateral diffusion of photocarriers by enhancing recombination. A device simulation verified that a higher spatial resolution could be obtained by adjusting the gap between the modulated and constant light. It was also found that a higher intensity and a longer wavelength of constant light was more effective. However, there exists a tradeoff between the spatial resolution and the amplitude of the photocurrent, and thus, the signal-to-noise ratio. A tilted incidence of constant light was applied, which could achieve even higher resolution with a smaller loss of photocurrent.},
  language  = {en}
}