印象中Q>1。

以下是wiki中关于日本JT-60U的一段：

On October 31, 1996, JT-60U successfully achieved extrapolated breakeven with a factor of Q_DT^eq = 1.05 at 2.8 MA. In other words, if the homogenous deuterium fuel was theoretically replaced with a 1:1 mix of deuterium and tritium, the fusion reaction would have created an energy output 1.05 times the energy used to start the reaction. JT-60U was not equipped to utilize tritium, as it would add extensive costs and safety risks.

也就是说当时用的D-D反应。等价D-T反应的话，Q>1。后来的实验更进了一步，但应该一直没有用T。

没有记错的话，英国的一个托卡马克也做过类似实验。