Analogously to 3D case this wave function is nearly equal to the potential well wave function ∝ exp( − kr ) $_{/}$√$_{r}$ where k = 〈√ 2 m | E | + U 〉 / ¯ h which differs from k$_{0}$ = √ 2 m | E | / ¯ h only in the second order of U/E . Now let us consider negative magnetoresistance related to the interference contribution to the hopping probability. Following the same lines as for 3D case we obtain the equation similar to 14 except that the integration is over d $^{2}$r$_{3}$ and the density of states g also corre- sponds to 2D. An important difference is related to the fact that now the value of J vanishes at With a similar transformation of the variables the integration of the logarithmic term over the coordinates gives while the effective loop area is ( r$_{min}$ E 2 B E 2 3 ) 3 / 2 a 1 / $^{2}$ϕ (26) r$_{23}$ = r$_{min}$ ( E $_{B}$/E$_{3}$ ) 2 (25) r$_{12}$ ( r$_{min}$ ( E B E$_{3}$ ) 2 a ) 1 / 2 (27) Since in 2D in the Coulomb gap regime g ∝ ε one notes that irrespectively to the hopping law the integration over E$_{3}$ is controlled by the lower possible values of E$_{3}$ leading finally to the estimates of r$_{23}$ ∼ r$_{12}$ . Thus one obtains Thus, at is seen, for the situation considered above in 2D the only combination of interference NMR and wave-shrinkage PMR can not lead to a suppression of NMR with a decrease of temperature (at least for low temperature limit of linear NMR) since for both laws the temperature derivative of k stays to be negative. An important feature of the 2D quantum well structure is an easy possibility to have an occupation of the upper Hubbard band. Namely, if we dope not only the well regions, but also the barrier regions, the carriers from the barriers are captured by the wells and can form doubly occupied states. It was this situation which was realized in our experiments described in [11], [12]. Since in these experiments we dealt with GaAs/AlGaAs structures of quantum wells with p-doping by Be, here we will also imply acceptor centers. k$_{2}$ = g$_{M}$ E $_{B}$r 1 / 2 $_{min}$r$_{h}$ 2 a 1 / $^{2}$α1 / 2 Mott law k$_{2}$ = κ 2 e 4 E 2 $_{B}$r$_{min}$ r 1 / 2 h 2 a 1 / $^{2}$α1 / 2 ES law (28) 10