Next, having learned from the ARES experiments that it is indeed possible to increase CNT yield by controlling the cooling rate and temperature, and aiming to assess the scalability of the concept, we turned to non-isothermal growth in a conventional tube furnace-based CVD system. The biggest difference between ARES and conventional CVD is the laser, whose power can be controlled such that the temperature can be varied quickly (manually or through computer control), thus enabling very high heating/cooling rates. This is difficult in a standard reactor run by proportional-integral-derivative (PID) temperature control and therefore puts limits on the nonisothermal cooling rate that can be achieved. In our conventional CVD experiments, we reduced the temperature of our tube furnace (Lindberg Blue/M Mini Mite) by manually setting Tf after it had heated up to Ti. The temperature controller was able to reduce the temperature by either 50 or 100 ºC within approximately 3 minutes. While this cooling rate is longer than the optimal rates shown in Figure , we were nonetheless able to unambiguously highlight the power of nonisothermal growth on the CNT yield, as described below.