
Neoliberalism - the doctrine that market exchange is an ethic in itself, capable of acting as a guide for all human action - has become dominant in both thought and practice throughout much of the world since 1970 or so. Its spread has depended upon a reconstitution of state powers such that privatization, finance, and market processes are emphasized. State interventions in the economy are minimized, while the obligations of the state to provide for the welfare of its citizens are diminished. David Harvey, author of 'The New Imperialism' and 'The Condition of Postmodernity', here tells the political-economic story of where neoliberalization came from and how it proliferated on the world stage. While Thatcher and Reagan are often cited as primary authors of this neoliberal turn, Harvey shows how a complex of forces, from Chile to China and from New York City to Mexico City, have also played their part. In addition he explores the continuities and contrasts between neoliberalism of the Clinton sort and the recent turn towards neoconservative imperialism of George W. Bush. Finally, through critical engagement with this history, Harvey constructs a framework not only for analyzing the political and economic dangers that now surround us, but also for assessing the prospects for the more socially just alternatives being advocated by many oppositional movements.
https://www.jacobinmag.com/2016/07/david-harvey-neoliberalis...
I do not consider neoliberalism to be a modern Marxist invention, though I can't claim to know about its history, and of course hitsory is extremely important to reveal a movement's origin and aims. My reasoning is from the idea that neoliberalism supports private property and what Marxists see as a class society. It does not aim for the abolition of these classes, but rather its stated goal is to acheive development within the capitalist system.
In this way, neoliberalism is identical to social democracy in its overall aim - it works within a class society to try and bring better conditions, though people frequently criticise neoliberalism as being uncaring of the poor, the Marxist would say a similar thing about social democracy.
For a read by a thinker inspired by Marx, I've heard good things about David Harvey's A Brief History of Neoliberalism. I have not read it, so I don't know if I should recommend it, but since you mentioned modern Marxists, and he is one, it may be of some use to you.
[0] https://newleftreview.org/II/49/alain-badiou-the-communist-h...
Read David Harvey's A Brief History of Neoliberalism (http://www.amazon.com/Brief-History-Neoliberalism-David-Harv...) for a stunning exposition of the social and economic crises that have developed around the world as a result of governments attempting to apply this philosophy.