We report on our searches for debris disks around seven relatively nearby radio pulsars, which are isolated sources and were carefully selected as the targets on the basis of our deep $K_s$-band imaging survey. The $K_s$ images obtained with the 6.5,m Baade Magellan Telescope at Las Campanas Observatory are analyzed together with the textit{Spitzer}/IRAC images at 4.5 and 8.0~$mu$m and the textit{WISE} images at 3.4, 4.6, 12 and 22~$mu$m. No infrared (IR) counterparts of these pulsars are found, with flux upper limits of $sim mu$Jy at near-infrared ($lambda<10 mu$m) and $sim$10--1000,$mu$Jy at mid-infrared wavelengths ($lambda>10 mu$m). The results of this search are discussed in terms of the efficiency of converting the pulsar spin-down energy to thermal energy and X-ray heating of debris disks, with comparison made to the two magnetars 4U~0142+61 and 1E~2259+586 which are suggested to harbor a debris disk.
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