## 3 Results and Discussion
### Results of the Experimental Study and Their Interpretation
Note the structure of a 1 \(\upmu\)m cell period with the localization of the electrostatic field [5], the measured photo current rates for the fixed bias voltages showed a significant non-linear increase with an increase in the optical power. In our view, the reason for such photo current behavior could be extremely high levels of the form-factor and small inter-tip distances. As a result of intensified near-field effects (localization of the optical field on the nanoscale tips), redistribution of the concentration of hot electrons can lead to the nonlinear effects of electron-electron and electron-phonon interactions. Linearity of the photo current-optical power characteristics of the proposed and investigated photosensor is estimated as preferable for the majority of optical-electronic applications. Known devices based on arrays of gold plasmon nanosized elements can be mentioned as similar photosensors: in the form of \"mushrooms\" [6] and in the form of a triangular unit-cell on adjacent rows [5]. In both cases, the effect of local surface plasmon resonance of gold nanostructures is used. On the basis of a theoretical analysis, the above studies show that the electric field enhancement can reach 100-120 only at certain resonant frequencies. The experimental data on the study of the photoeffect in a vacuum diode are presented for two wavelengths of 633 and 785 nm in the work of [6] and for one value \(\lambda\) = 785 nm in the work of [5]. A feature of the nanostructure [5] is a very small vacuum gap between adjacent opposite points, which is 50 nm. The photoeffect is observed while ensuring the electric field in the gap at a level of up to 1 GV/m. When the field was varied, a photocurrent of 0.3-8 \(\upmu\)A was detected upon irradiation with a laser beam with an intensity of 0.2 kW/cm\({}^{2}\). The analysis of the results of the study of the photosensor in this article allows us to determine the intensity of the working field. The photoeffect is detected at a field of 0.22-0.24 GV/m. The magnitude of the photocurrent in this case varies in the range 0.3-5.8 \(\upmu\)A (see Figure 8a), which approximately corresponds to the level of the photoresponse of the analog [5]. Along with the broadband of the studied photosensor, it is necessary to note the following additional advantages in comparison with analogues:  
1. The simplicity and low cost of manufacturing technology (traditional photolithography compared with e-beam lithography, molybdenum instead of gold). 2. The \"open\" structure of the photosensor electrodes allows the formation of a directed electron flow from the tip of the blade into the free space. This is important for creating current sources for vacuum devices (X-ray tubes, UHF (Ultra high frequency) and THz (Terahertz) generators, and amplifiers) with ultrafast optical signal modulation. In known analogues with nanoscale vacuum gap, the possibility of forming an electron flow with a controlled trajectory is associated with great difficulties. Figure 9: Dependence of the photocurrent of the vacuum sensor with a molybdenum blade sensing element on the laser pulse energy; the wavelength of the irradiating beam is 540 nm.